Exposure apparatus, exposure method, and method for producing device

ABSTRACT

Exposure apparatus exposes a substrate by irradiating the substrate with exposure light via a projection optical system and a liquid. The exposure apparatus is provided with a liquid immersion mechanism for supplying the liquid and recovering the liquid. The liquid immersion mechanism has an inclined surface, which is opposite to a surface of the substrate and is inclined with respect to the surface of the substrate, and a liquid recovering port of the liquid immersion mechanism is formed in the inclined surface. A flat portion is provided between the substrate and the projection optical system. A liquid immersion area can be maintained to be small.

This application is a continuation of U.S. patent application Ser. No.15/367,348 filed Dec. 2, 2016, which is a division of U.S. patentapplication Ser. No. 14/823,673 filed Aug. 11, 2015, which is acontinuation of U.S. patent application Ser. No. 13/936,793 filed Jul.8, 2013, which is a division of U.S. patent application Ser. No.11/597,745 filed Dec. 22, 2006, which is a U.S. National Stage ofPCT/JP2005/010576 filed Jun. 9, 2005. The disclosures of each of theprior applications are hereby incorporated by reference herein in theirentireties.

TECHNICAL FIELD

The present invention relates to an exposure apparatus and an exposuremethod in which a substrate is exposed through a liquid, and a methodfor producing a device.

BACKGROUND ART

Semiconductor devices and liquid crystal display devices are produced bythe so-called photolithography technique in which a pattern formed on amask is transferred onto a photosensitive substrate. The exposureapparatus, which is used in the photolithography step, includes a maskstage for supporting the mask and a substrate stage for supporting thesubstrate. The pattern on the mask is transferred onto the substrate viaa projection optical system while successively moving the mask stage andthe substrate stage. In recent years, it is demanded to realize thehigher resolution of the projection optical system in order to respondto the further advance of the higher integration of the device pattern.As the exposure wavelength to be used is shorter, the resolution of theprojection optical system becomes higher. As the numerical aperture ofthe projection optical system is larger, the resolution of theprojection optical system becomes higher. Therefore, the exposurewavelength, which is used for the exposure apparatus, is shortened yearby year, and the numerical aperture of the projection optical system isincreased as well. The exposure wavelength, which is dominantly used atpresent, is 248 nm of the KrF excimer laser. However, the exposurewavelength of 193 nm of the ArF excimer laser, which is shorter than theabove, is also practically used in some situations. When the exposure isperformed, the depth of focus (DOF) is also important in the same manneras the resolution. The resolution R and the depth of focus δ arerepresented by the following expressions respectively.

R=k ₁ ·λ/NA  (1)

δ=±k ₂ ·λ/NA ²  (2)

In the expressions, λ represents the exposure wavelength, NA representsthe numerical aperture of the projection optical system, and k₁ and k₂represent the process coefficients. According to the expressions (1) and(2), the following fact is appreciated. That is, when the exposurewavelength λ is shortened and the numerical aperture NA is increased inorder to enhance the resolution R, then the depth of focus δ isnarrowed.

If the depth of focus δ is too narrowed, it is difficult to match thesubstrate surface with respect to the image plane of the projectionoptical system. It is feared that the focus margin is insufficientduring the exposure operation. Accordingly, the liquid immersion methodhas been suggested, which is disclosed, for example, in InternationalPublication No. 99/49504 as a method for substantially shortening theexposure wavelength and widening the depth of focus. In this liquidimmersion method, the space between the lower surface of the projectionoptical system and the substrate surface is filled with a liquid such aswater or any organic solvent to form a liquid immersion area so that theresolution is improved and the depth of focus is magnified about n timesby utilizing the fact that the wavelength of the exposure light beam inthe liquid is 1/n as compared with that in the air (n represents therefractive index of the liquid, which is about 1.2 to 1.6 in ordinarycases).

As disclosed in International Publication No. 99/49504 as describedabove, a scanning type exposure apparatus is known, in which thesubstrate is exposed with a pattern formed on the mask whilesynchronously moving the mask and the substrate in the scanningdirection. In the case of the scanning type exposure apparatus, it isrequired to realize the high scanning velocity (velocity of scanning) inorder to improve, for example, the productivity of device production.However, if the scanning velocity is increased to be high, then it isdifficult to maintain the desired state, for example, for the condition(for example, the size) of the liquid immersion area, and the exposureaccuracy and the measurement accuracy, which are to be obtained throughthe liquid, are consequently deteriorated. Therefore, it is requiredthat the liquid immersion area of the liquid is maintained to be in thedesired state even when the scanning velocity is increased to be high.

For example, if the liquid immersion area cannot be maintained in thedesired state, and any bubble and/or any void (gap) is formed in theliquid, then the exposure light beam, which passes through the liquid,does not arrive at the surface of the substrate satisfactorily due tothe bubble and/or the void, and an inconvenience arises, for example,such that any defect appears in the pattern to be formed on thesubstrate. When the liquid immersion area is locally formed on a part ofthe substrate while supplying and recovering the liquid, there is such apossibility that it is difficult to sufficiently recover the liquid ofthe liquid immersion area as the scanning velocity is increased to behigh. If the liquid cannot be recovered sufficiently, the adhesion trace(so-called water mark, the adhesion trace of the liquid will behereinafter referred to as “water mark” as well when the liquid is notwater) is formed, for example, due to the vaporization or evaporation ofthe liquid remaining on the substrate. There is such a possibility thatthe water mark exerts any influence on the photoresist on the substrate,and there is such a possibility that the performance of the device to beproduced is deteriorated by the influence. There is also such apossibility that it is difficult that the liquid immersion area ismaintained to have a desired size as the scanning velocity is increasedto be high. There is also such a possibility that the liquid of theliquid immersion area outflows as the scanning velocity is increased tobe high.

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

The present invention has been made taking the foregoing circumstancesinto consideration, an object of which is to provide an exposureapparatus, an exposure method, and a method for producing a device basedon the use of the exposure apparatus, wherein the exposure process canbe performed satisfactorily while maintaining the liquid immersion areato be in a desired state.

Means for Solving the Problem and Effect of the Invention

In order to achieve the object as described above, the present inventionadopts the following constructions corresponding to FIGS. 1 to 33 ascorresponding to embodiments.

According to a first aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by radiating an exposurelight beam onto the substrate through a liquid; the exposure apparatuscomprising a projection optical system; and a liquid immersion mechanismwhich supplies the liquid and which recovers the liquid; wherein theliquid immersion mechanism has an inclined surface which is opposite toa surface of the substrate and which is inclined with respect to thesurface of the substrate, and a liquid recovery port of the liquidimmersion mechanism is formed on the inclined surface.

According to the first aspect of the present invention, the liquidrecovery port of the liquid immersion mechanism is formed on theinclined surface which is opposed to the surface of the substrate.Therefore, even when the substrate and the liquid immersion area formedon the side of the image plane of the projection optical system arerelatively moved, it is possible to suppress any large change of theshape of the interface as well, while suppressing the amount of movementof the interface (gas-liquid interface) between the liquid of the liquidimmersion area and the space disposed at the outside thereof. Therefore,it is possible to maintain a desired state for the condition (forexample, the size) of the liquid immersion area. Further, it is possibleto suppress the spread or expansion of the liquid immersion area.

According to a second aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by radiating an exposurelight beam onto the substrate through a liquid; the exposure apparatuscomprising a projection optical system; and a liquid immersion mechanismwhich supplies the liquid and which recovers the liquid; wherein theliquid immersion mechanism has a flat portion which is formed oppositeto a surface of the substrate and which is formed to be substantially inparallel to the surface of the substrate; the flat portion of the liquidimmersion mechanism is arranged to surround a projection area onto whichthe exposure light beam is radiated, between the substrate and an endsurface on a side of an image plane of the projection optical system;and a liquid supply port of the liquid immersion mechanism is arrangedoutside the flat portion with respect to the projection area onto whichthe exposure light beam is radiated.

According to the second aspect of the present invention, the small gap,which is formed between the substrate surface and the flat portion, canbe formed in the vicinity of the projection area to surround theprojection area. Therefore, it is possible to maintain the small liquidimmersion area which is necessary and sufficient to cover the projectionarea. Additionally, the liquid, which forms the liquid immersion area,is prevented from the entrance and mixing of any gas into the liquid,because the liquid supply port is provided outside the flat portion.Thus, it is possible to continuously fill the optical path for theexposure light beam with the liquid.

According to a third aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by radiating an exposurelight beam onto the substrate through a liquid; the exposure apparatuscomprising a projection optical system; and a liquid immersion mechanismwhich supplies the liquid and which recovers the liquid; wherein theliquid immersion mechanism includes a liquid supply port which isprovided at a first position disposed outside an optical path space forthe exposure light beam and which supplies the liquid; and a guidemember which guides the liquid so that the liquid, supplied from theliquid supply port, flows toward a second position via the optical pathspace, the second position being different from the first positiondisposed outside the optical path space.

According to the third aspect of the present invention, the liquid,supplied from the liquid supply port provided at the first positiondisposed outside the optical path space for the exposure light beam, isallowed to flow, by the guide member, to the second position which isdifferent from the first position as disposed outside the optical pathspace. Therefore, it is possible to suppress the occurrence of anyinconvenience which would be otherwise caused, for example, such thatany gas portion (bubble) is formed in the liquid with which the opticalpath space for the exposure light beam is filled. It is possible tomaintain the desired state for the liquid.

According to a fourth aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by radiating an exposurelight beam onto the substrate through a liquid; the exposure apparatuscomprising an optical system which has an end surface opposite to thesubstrate and through which the exposure light beam to be radiated ontothe substrate passes; and a liquid immersion mechanism which suppliesthe liquid and which recovers the liquid; wherein the liquid immersionmechanism includes a plate member which is arranged opposite and inparallel to the substrate between the substrate and the end surface ofthe optical system and which has a flat surface arranged to surround anoptical path for the exposure light beam; and the liquid is supplied, toa space between the plate member and the end surface of the opticalsystem, from a supply port which is provided in the vicinity of the endsurface of the optical system, and the liquid is recovered from arecovery port which is arranged opposite to the substrate at a positionseparated farther from the optical path for the exposure light beam thanthe flat surface of the plate member.

According to the exposure apparatus of the fourth aspect of the presentinvention, the minute gap is formed between the substrate and the flatsurface of the plate member to surround the exposure light beam.Further, the recovery port for the liquid is arranged outside the flatsurface. Therefore, the liquid immersion area, which is stable in adesired state, can be maintained on the substrate. Further, the liquidis supplied to the space between the plate member and the end surface ofthe optical system. Therefore, the bubble and the void (gap) are hardlyformed in the liquid immersion area formed on the optical path for theexposure light beam.

According to a fifth aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by radiating an exposurelight beam onto the substrate through a liquid; the exposure apparatuscomprising an optical member which has an end surface making contactwith the liquid and through which the exposure light beam passes; and aliquid immersion mechanism which supplies the liquid and which recoversthe liquid; wherein the liquid immersion mechanism includes a flatsurface which is arranged opposite and in parallel to the substrate tosurround an optical path for the exposure light beam, and an inclinedsurface which is inclined with respect to the flat surface and isdisposed outside the flat surface with respect to the optical path forthe exposure light beam.

According to the exposure apparatus of the fifth aspect of the presentinvention, the minute gap is formed between the substrate and the flatsurface of the plate member to surround the exposure light beam.Therefore, the liquid immersion area, which is stable in a desiredstate, can be maintained on the substrate. Further, the inclined surfaceis formed outside the flat surface. Therefore, the liquid is suppressedfrom any spread, and it is possible to avoid, for example, any leakageof the liquid.

According to a sixth aspect of the present invention, there is providedan exposure method for exposing a substrate by radiating an exposurelight beam onto the substrate via an optical member and a liquid; theexposure method comprising arranging the substrate so that the substrateis opposite to an end surface of the optical member; supplying theliquid to a space between the end surface of the optical member and onesurface of a plate member arranged to surround an optical path for theexposure light beam between the substrate and the end surface of theoptical member so as to fill, with the liquid, a space between thesubstrate and the end surface of the optical member and a space betweenthe substrate and the other surface of the plate member; forming aliquid immersion area on a part of the substrate by recovering theliquid from a recovery port arranged opposite to the substrateconcurrently with supply of the liquid; and exposing the substrate byradiating the exposure light beam onto the substrate through the liquidwith which the liquid immersion area is formed on the part of thesubstrate.

According to the exposure method of the sixth aspect of the presentinvention, the minute gap is formed between the substrate and the flatsurface of the plate member to surround the exposure light beam.Therefore, the desired liquid immersion area, which is stable, can bemaintained on the substrate. Further, the liquid is supplied to thespace between the plate member and the end surface of the opticalmember. Therefore, it is possible to suppress the formation of thebubble and the void in the liquid disposed in the optical path for theexposure light beam.

According to a seventh aspect of the present invention, there isprovided a method for producing a device, comprising using the exposureapparatus as defined in any one of the aspects described above.

According to the seventh aspect of the present invention, the exposureprocess can be performed satisfactorily in a state in which the liquidimmersion area of the liquid is maintained in a desired condition, evenwhen the scanning velocity is increased to be high. Therefore, thedevice having the desired performance can be produced at a highproduction efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic arrangement illustrating a first embodiment ofthe exposure apparatus of the present invention.

FIG. 2 shows a schematic perspective view illustrating those disposed inthe vicinity of a nozzle member according to the first embodiment.

FIG. 3 shows a perspective view illustrating the nozzle member accordingto the first embodiment as viewed from the lower side.

FIG. 4 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the first embodiment.

FIG. 5 shows a schematic arrangement illustrating an embodiment of aliquid recovery mechanism.

FIG. 6 schematically illustrates the principle of the liquid recoveryoperation performed by the liquid recovery mechanism.

FIGS. 7(a) and 7(b) schematically illustrate the liquid recoveryoperation according to the first embodiment.

FIGS. 8(a) and 8(b) schematically illustrate comparative examples of theliquid recovery operation.

FIG. 9 schematically shows a nozzle member according to a secondembodiment.

FIG. 10 schematically shows a nozzle member according to a thirdembodiment.

FIG. 11 schematically shows a nozzle member according to a fourthembodiment.

FIG. 12 shows a perspective view illustrating a nozzle member accordingto a fifth embodiment as viewed from the lower side.

FIG. 13 shows a schematic perspective view illustrating those disposedin the vicinity of a nozzle member according to a sixth embodiment.

FIG. 14 shows a perspective view illustrating the nozzle memberaccording to the sixth embodiment as viewed from the lower side.

FIG. 15 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the sixth embodiment.

FIG. 16 illustrates the function of the nozzle member according to thesixth embodiment.

FIG. 17 shows a perspective view illustrating a nozzle member accordingto a seventh embodiment as viewed from the lower side.

FIG. 18 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the seventh embodiment.

FIG. 19 shows a schematic perspective view illustrating those disposedin the vicinity of a nozzle member according to an eighth embodiment.

FIG. 20 shows a perspective view illustrating the nozzle memberaccording to the eighth embodiment as viewed from the lower side.

FIG. 21 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the eighth embodiment.

FIG. 22 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the eighth embodiment.

FIG. 23 shows a guide member according to the eighth embodiment.

FIG. 24 shows a side sectional view illustrating those disposed in thevicinity of the nozzle member according to the eighth embodiment.

FIG. 25 shows a plan view illustrating a guide member according to aninth embodiment.

FIG. 26 shows a plan view illustrating a guide member according to atenth embodiment.

FIG. 27 shows a plan view illustrating a guide member according to aneleventh embodiment.

FIG. 28 shows a plan view illustrating a guide member according to atwelfth embodiment.

FIG. 29 shows a plan view illustrating a guide member according to athirteenth embodiment.

FIG. 30 shows a plan view illustrating a guide member according to afourteenth embodiment.

FIG. 31 shows a plan view illustrating a guide member according to afifteenth embodiment.

FIG. 32 shows a plan view illustrating a guide member according to asixteenth embodiment.

FIG. 33 shows a flow chart illustrating exemplary steps of producing asemiconductor device.

LEGENDS OF REFERENCE NUMERALS

-   -   1: liquid immersion mechanism, 2: inclined surface, 12: liquid        supply port, 22: liquid recovery port, 25: porous member, 70,        70′, 70″: nozzle member, 71D, 72D: bottom plate portion        (plate-shaped member), 73: groove, 73A: opening, 74, 74′:        opening, 75: land surface (flat portion), 76: wall portion,        130A: gas discharge port, 135: suction unit (suction system),        140A: liquid supply port, 172D: bottom plate portion (member,        guide member), 181: first guide portion, 181F: flow passage,        182: second guide portion, 182F: flow passage, AR1: projection        area, AR2: liquid immersion area, AX: optical axis, EL: exposure        light beam, EX: exposure apparatus, G2: gap (space), LQ: liquid,        P: substrate, PL: projection optical system, T1: end surface.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be explained below withreference to the drawings. However, the present invention is not limitedthereto.

First Embodiment

FIG. 1 shows a schematic arrangement illustrating a first embodiment ofthe exposure apparatus according to the present invention. Withreference to FIG. 1, the exposure apparatus EX includes a mask stage MSTwhich is movable while holding a mask M, a substrate stage PST which ismovable while holding a substrate P, an illumination optical system ILwhich illuminates, with an exposure light beam EL, the mask M held bythe mask stage MST, a projection optical system PL which projects animage of a pattern of the mask M illuminated with the exposure lightbeam EL onto the substrate P held by the substrate stage PST to performthe exposure, and a control unit CONT which integrally controls theoperation of the entire exposure apparatus EX.

The exposure apparatus EX of the embodiment of the present invention isthe liquid immersion exposure apparatus in which the liquid immersionmethod is applied in order that the exposure wavelength is substantiallyshortened to improve the resolution and the depth of focus issubstantially widened. The exposure apparatus EX includes a liquidimmersion mechanism 1 which supplies the liquid LQ and which recoversthe liquid LQ. The liquid immersion mechanism 1 includes a liquid supplymechanism 10 which supplies the liquid LQ to the side of the image planeof the projection optical system PL, and a liquid recovery mechanism 20which recovers the liquid LQ supplied by the liquid supply mechanism 10.The exposure apparatus EX forms a liquid immersion area AR2 locally onat least a part of the substrate P including a projection area AR1 ofthe projection optical system PL by the liquid LQ supplied from theliquid supply mechanism 10 at least during the period in which the imageof the pattern of the mask M is being transferred onto the substrate P,the liquid immersion area AR2 being larger than the projection area AR1and smaller than the substrate P. Specifically, the exposure apparatusEX adopts the local liquid immersion system in which the space betweenan optical element LS1 disposed at the end portion on the side of theimage plane of the projection optical system PL and the substrate Parranged on the side of the image plane is filled with the liquid LQ.The substrate P is subjected to the projection exposure with the patternof the mask M by radiating the exposure light beam EL allowed to passthrough the mask M, via the projection optical system PL and the liquidLQ disposed between the projection optical system PL and the substrateP. The control unit CONT forms the liquid immersion area AR2 of theliquid LQ locally on the substrate P by supplying a predetermined amountof the liquid LQ onto the substrate P by using the liquid supplymechanism 10 and recovering a predetermined amount of the liquid LQdisposed on the substrate P by using the liquid recovery mechanism 20.

A nozzle member 70 is arranged as described in detail later on, in thevicinity of the image plane of the projection optical system PL,specifically in the vicinity of the optical element LS1 disposed at theend on the side of the image plane of the projection optical system PL.The nozzle member 70 is an annular member which is provided to surroundthe optical element LS1 over or at a position above the substrate P(substrate stage PST). In the embodiment of the present invention, thenozzle member 70 constructs a part of the liquid immersion mechanism 1.

The embodiment of the present invention will now be explained asexemplified by a case of the use of the scanning type exposure apparatus(so-called scanning stepper) as the exposure apparatus EX in which thesubstrate P is exposed with the pattern formed on the mask M whilesynchronously moving the mask M and the substrate P in mutuallydifferent directions (opposite directions) in the scanning directions(predetermined directions). In the following explanation, the Z axisdirection is the direction which is coincident with the optical axis AXof the projection optical system PL, the X axis direction is thesynchronous movement direction (scanning direction) for the mask M andthe substrate P in the plane perpendicular to the Z axis direction, andthe Y axis direction (non-scanning direction) is the direction which isperpendicular to the Z axis direction and the X axis direction. Thedirections of rotation (inclination) about the X axis, the Y axis, andthe Z axis are designated as θX, θY, and θZ directions respectively.

The exposure apparatus EX includes a base BP which is provided on thefloor surface, and a main column 9 which is installed on the base BP.The main column 9 is provided with an upper stepped portion 7 and alower stepped portion 8 which protrude inwardly. The illuminationoptical system IL is provided so that the mask M, which is supported onthe mask stage MST, is illuminated with the exposure light beam EL. Theillumination optical system IL is supported by a support frame 3 whichis fixed to an upper portion of the main column 9.

The illumination optical system IL includes, for example, an exposurelight source, an optical integrator which uniformizes the illuminance ofthe light flux radiated from the exposure light source, a condenser lenswhich collects the exposure light beam EL emitted from the opticalintegrator, a relay lens system, and a variable field diaphragm whichsets the illumination area on the mask M illuminated with the exposurelight beam EL to be slit-shaped. The predetermined illumination area onthe mask M is illuminated with the exposure light beam EL having auniform illuminance distribution by the illumination optical system IL.Those usable as the exposure light beam EL radiated from theillumination optical system IL include, for example, emission lines(g-ray, h-ray, i-ray) radiated, for example, from a mercury lamp, farultraviolet light beams (DUV light beams) such as the KrF excimer laserbeam (wavelength: 248 nm), and vacuum ultraviolet light beams (VUV lightbeams) such as the ArF excimer laser beam (wavelength: 193 nm) and theF₂ laser beam (wavelength: 157 nm). In this embodiment, the ArF excimerlaser beam is used.

In this embodiment, pure or purified water is used as the liquid LQ. Notonly the ArF excimer laser but also the emission line (g-ray, h-ray,i-ray) radiated, for example, from a mercury lamp and the farultraviolet light beam (DUV light beam) such as the KrF excimer laserbeam (wavelength: 248 nm) are also transmissive through pure water.

The mask stage MST is movable while holding the mask M. The mask stageMST holds the mask M by the vacuum attraction (or the electrostaticattraction). A plurality of gas bearings (air bearings) 85, which arenon-contact bearings, are provided on the lower surface of the maskstage MST. The mask stage MST is supported in a non-contact manner withrespect to the upper surface (guide surface) of a mask surface plate 4by the air bearings 85. Openings MK1, MK2, through which the image ofthe pattern of the mask M is allowed to pass, are formed at centralportions of the mask stage MST and the mask surface plate 4respectively. The mask surface plate 4 is supported by the upper steppedportion 7 of the main column 9 by the aid of an anti-vibration unit 86.That is, the mask stage MST is supported by the main column 9 (upperstepped portion 7) by the aid of the anti-vibration unit 86 and the masksurface plate 4. The mask surface plate 4 and the main column 9 areisolated from each other in terms of the vibration by the anti-vibrationunit 86 so that the vibration of the main column 9 is not transmitted tothe mask surface plate 4 which supports the mask stage MST.

The mask stage MST is two-dimensionally movable in the planeperpendicular to the optical axis AX of the projection optical systemPL, i.e., in the XY plane, and it is finely rotatable in the θZdirection on the mask surface plate 4 in a state in which the mask M isheld, in accordance with the driving operation of the mask stage-drivingunit MSTD including, for example, a linear motor controlled by thecontrol unit CONT. The mask stage MST is movable at a designatedscanning velocity in the X axis direction. The mask stage MST has amovement stroke in the X axis direction to such an extent that theentire surface of the mask M traverses at least the optical axis AX ofthe projection optical system PL.

A movement mirror 81, which is movable together with the mask stage MST,is provided on the mask stage MST. A laser interferometer 82 is providedat a position opposed to the movement mirror 81. The position in thetwo-dimensional direction and the angle of rotation in the θZ direction(including angles of rotation in the θX and θY directions in some cases)of the mask M on the mask stage MST are measured in real-time by thelaser interferometer 82. The result of the measurement of the laserinterferometer 82 is outputted to the control unit CONT. The controlunit CONT drives the mask stage-driving unit MSTD on the basis of theresult of the measurement obtained by the laser interferometer 82 tothereby control the position of the mask M held by the mask stage MST.

The projection optical system PL projects the pattern of the mask M ontothe substrate P at a predetermined projection magnification β to performthe exposure. The projection optical system PL includes a plurality ofoptical elements including the optical element LS1 provided at the endportion on the side of the substrate P. The optical elements aresupported by a barrel PK. In this embodiment, the projection opticalsystem PL is based on the reduction system in which the projectionmagnification β is, for example, ¼, ⅕, or ⅛. The projection opticalsystem PL may be any one of the 1× magnification system and themagnifying system. The projection optical system PL may be any one ofthe catadioptric system including dioptric and catoptric elements, thedioptric system including no catoptric element, and the catoptric systemincluding no dioptric element. The optical element LS1, which isdisposed at the end portion of the projection optical system PL of thisembodiment, is exposed from the barrel PK. The liquid LQ of the liquidimmersion area AR2 makes contact with the optical element LS1.

A flange PF is provided on the outer circumference of the barrel PKwhich holds the projection optical system PL. The projection opticalsystem PL is supported by a barrel surface plate 5 by the aid of theflange PF. The barrel surface plate 5 is supported by the lower steppedportion 8 of the main column 9 by the aid of an anti-vibration unit 87.That is, the projection optical system PL is supported by the maincolumn 9 (lower stepped portion 8) by the aid of the anti-vibration unit87 and the barrel surface plate 5. The barrel surface plate 5 isisolated from the main column 9 in terms of vibration by theanti-vibration unit 87 so that the vibration of the main column 9 is nottransmitted to the barrel surface plate 5 which supports the projectionoptical system PL.

The substrate stage PST is movable while supporting the substrate holderPH which holds the substrate P. The substrate holder PH holds thesubstrate P, for example, by the vacuum attraction. A plurality of gasbearings (air bearings) 88, which are the non-contact bearings, areprovided on the lower surface of the substrate stage PST. The substratestage PST is supported in a non-contact manner by the air bearings 88with respect to the upper surface (guide surface) of the substratesurface plate 6. The substrate surface plate 6 is supported on the baseBP by the aid of an anti-vibration unit 89. The substrate surface plate6 is isolated from the main column 9 and the base BP (floor surface) interms of vibration by the anti-vibration unit 89 so that the vibrationsof the base BP (floor surface) and the main column 9 are not transmittedto the substrate surface plate 6 which supports the substrate stage PST.

The substrate stage PST is two-dimensionally movable in the XY plane,and it is finely rotatable in the θZ direction on the substrate surfaceplate 6 in a state in which the substrate P is held by the aid of thesubstrate holder PH, in accordance with the driving operation of thesubstrate stage-driving unit PSTD including, for example, the linearmotor which is controlled by the control unit CONT. Further, thesubstrate stage PST is also movable in the Z axis direction, the θXdirection, and the θY direction.

A movement mirror 83, which is movable together with the substrate stagePST with respect to the projection optical system PL, is provided on thesubstrate stage PST. A laser interferometer 84 is provided at a positionopposed to the movement mirror 83. The angle of rotation and theposition in the two-dimensional direction of the substrate P on thesubstrate stage PST are measured in real-time by the laserinterferometer 84. Although not shown, the exposure apparatus EX isprovided with a focus/leveling-detecting system which detects theposition information about the surface of the substrate P supported bythe substrate stage PST. Those adoptable as the focus/leveling-detectingsystem include, for example, those based on the oblique incidence systemin which the detecting light beam is radiated in an oblique directiononto the surface of the substrate P, and the system which uses anelectrostatic capacity type sensor. The focus/leveling-detecting systemdetects the position information in the Z axis direction about thesurface of the substrate P, and the information about the inclination inthe θX and θY directions of the substrate P through the liquid LQ or notthrough the liquid LQ. In the case of the focus/leveling-detectingsystem in which the surface information about the surface of thesubstrate P is detected not through the liquid LQ, the surfaceinformation about the surface of the substrate P may be detected at aposition separated or away from the projection optical system PL. Anexposure apparatus, in which the surface information about the surfaceof the substrate P is detected at the position separated or away fromthe projection optical system PL, is disclosed, for example, U.S. Pat.No. 6,674,510, contents of which are incorporated herein by referencewithin a range of permission of the domestic laws and ordinances of thestate designated or selected in this international application.

The result of the measurement performed by the laser interferometer 84is outputted to the control unit CONT. The result of the measurementperformed by the focus/leveling-detecting system is also outputted tothe control unit CONT. The control unit CONT drives the substratestage-driving unit PSTD on the basis of the detection result of thefocus/leveling-detecting system to control the angle of inclination andthe focus position of the substrate P so that the surface of thesubstrate P is adjusted to match the image plane of the projectionoptical system PL. Further, the control unit CONT controls the positionof the substrate P in the X axis direction and the Y axis direction onthe basis of the measurement result of the laser interferometer 84.

A recess 90 is provided on the substrate stage PST. The substrate holderPH for holding the substrate P is arranged in the recess 90. The uppersurface 91 other than the recess 90 of the substrate stage PST forms aflat surface (flat portion) which has approximately the same height asthat of (is flush with) the surface of the substrate P held by thesubstrate holder PH. Further, in this embodiment, the upper surface ofthe movement mirror 83 is also provided to be substantially flush withthe upper surface 91 of the substrate stage PST.

The liquid immersion area AR2 can be satisfactorily formed whileretaining the liquid LQ on the side of the image plane of the projectionoptical system PL, because the upper surface 91, which is substantiallyflush with the surface of the substrate P, is provided around thesubstrate P, and hence any difference in height is absent outside theedge portion of the substrate P, even when the edge area of thesubstrate P is subjected to the liquid immersion exposure. A gap ofabout 0.1 to 2 mm is formed between the edge portion of the substrate Pand the flat surface (upper surface) 91 provided around the substrate P.However, the liquid LQ hardly flows into the gap owing to the surfacetension of the liquid LQ. The liquid LQ can be retained under or belowthe projection optical system PL by the aid of the upper surface 91 evenwhen the portion, which is disposed in the vicinity of thecircumferential edge of the substrate P, is subjected to the exposure.

The liquid supply mechanism 10 of the liquid immersion mechanism 1supplies the liquid LQ to the image plane side of the projection opticalsystem PL. The liquid supply mechanism 10 includes a liquid supplysection 11 which is capable of feeding the liquid LQ, and a supply tube13 which has one end connected to the liquid supply section 11. Theother end of the supply tube 13 is connected to the nozzle member 70. Inthis embodiment, the liquid supply mechanism 10 supplies pure water. Theliquid supply section 11 includes, for example, a pure water-producingunit, and a temperature-adjusting unit which adjusts the temperature ofthe liquid (pure water) LQ to be supplied. On condition that apredetermined water quality condition is satisfied, a purewater-producing apparatus (utility power), which is provided in afactory for arranging the exposure apparatus EX therein, may be usedinstead of providing the pure water-producing unit for the exposureapparatus EX. Any equipment of the factory or the like may besubstitutively used instead of providing the temperature-adjusting unitfor adjusting the temperature of the liquid (pure water) LQ for theexposure apparatus EX as well. The operation of the liquid supplymechanism 10 (liquid supply section 11) is controlled by the controlunit CONT. In order to form the liquid immersion area AR2 on thesubstrate P, the liquid supply mechanism 10 supplies a predeterminedamount of the liquid LQ onto the substrate P arranged on the side of theimage plane of the projection optical system PL under or below thecontrol of the control unit CONT.

A flow rate controller 16 called “mass flow controller”, which controlsthe amount of the liquid per unit time to be fed from the liquid supplysection 11 and supplied to the image plane side of the projectionoptical system PL, is provided at an intermediate position of the supplytube 13. The control of the liquid supply amount based on the use of theflow rate controller 16 is performed under an instruction signal of thecontrol unit CONT.

The liquid recovery mechanism 20 of the liquid immersion mechanism 1 isprovided to recover the liquid LQ on the side of the image plane of theprojection optical system PL. The liquid recovery mechanism 20 includesa liquid recovery section 21 which is capable of recovering the liquidLQ, and a recovery tube 23 which has one end connected to the liquidrecovery section 21. The other end of the recovery tube 23 is connectedto the nozzle member 70. The liquid recovery section 21 includes, forexample, a vacuum system (suction unit) such as a vacuum pump, agas/liquid separator for separating the gas and the recovered liquid LQfrom each other, a tank for accommodating the recovered liquid LQ, andthe like. It is also allowable to use, for example, the equipment of thefactory in which the exposure apparatus EX is installed, instead ofproviding at least a part or parts of, for example, the vacuum system,the gas/liquid separator, the tank for the exposure apparatus EX, andthe like. The operation of the liquid recovery mechanism 20 (liquidrecovery section 21) is controlled by the control unit CONT. In order toform the liquid immersion area AR2 on the substrate P, the liquidrecovery mechanism 20 recovers a predetermined amount of the liquid LQon the substrate P supplied from the liquid supply mechanism 10 underthe control of the control unit CONT.

The nozzle member 70 is held by a nozzle holder 92. The nozzle holder 92is connected to the lower stepped portion 8 of the main column 9. Themain column 9, which supports the nozzle member 70 by the aid of thenozzle holder 92, is isolated in terms of vibration by theanti-vibration unit 87 from the barrel surface plate 5 which supportsthe barrel PK of the projection optical system PL by the aid of theflange PF. Therefore, the vibration, which is generated on the nozzlemember 70, is prevented from being transmitted to the projection opticalsystem PL. The main column 9, which supports the nozzle member 70 by theaid of the nozzle holder 92, is isolated in terms of vibration by theanti-vibration unit 89 from the substrate surface plate 6 which supportsthe substrate stage PST. Therefore, the vibration, which is generated onthe nozzle member 70, is prevented from being transmitted to thesubstrate stage PST via the main column 9 and the base BP. Further, themain column 9, which supports the nozzle member 70 by the aid of thenozzle holder 92, is isolated in terms of vibration by theanti-vibration unit 86 from the mask surface plate 4 which supports themask stage MST. Therefore, the vibration, which is generated on thenozzle member 70, is prevented from being transmitted to the mask stageMST via the main column 9.

Next, an explanation will be made with reference to FIGS. 2, 3, and 4about the liquid immersion mechanism 1 and the nozzle member 70 whichconstructs a part of the liquid immersion mechanism 1. FIG. 2 shows,with partially broken illustration, a schematic perspective viewillustrating those disposed in the vicinity of the nozzle member 70.FIG. 3 shows a perspective view illustrating the nozzle member 70 asviewed from the lower side. FIG. 4 shows a side sectional view of thenozzle member 70.

The nozzle member 70 is arranged in the vicinity of the optical elementLS1 disposed at the end portion on the side of the image plane of theprojection optical system PL. The nozzle member 70 is the annular memberwhich is provided to surround the optical element LS1 over or above thesubstrate P (substrate stage PST). The nozzle member 70 has a hole 70Hwhich is disposed at a central portion thereof and in which theprojection optical system PL (optical element LS1) can be arranged. Agap is provided between the inner side surface of the hole 70H of thenozzle member 70 and the side surface of the optical element LS1 of theprojection optical system PL. The gap is formed in order that theoptical element LS1 of the projection optical system PL is isolated interms of vibration from the nozzle member 70. Accordingly, thevibration, which is generated on the nozzle member 70, is prevented frombeing directly transmitted to the projection optical system PL (opticalelement LS1).

The inner side surface of the hole 70H of the nozzle member 70 isliquid-repellent (water-repellent) with respect to the liquid LQ, whichsuppresses the inflow of the liquid LQ into the gap between the sidesurface of the projection optical system PL and the inner side surfaceof the nozzle member 70.

Those formed on the lower surface of the nozzle member 70 include aliquid supply port 12 for supplying the liquid LQ and a liquid recoveryport 22 for recovering the liquid LQ. A supply flow passage 14 connectedto the liquid supply port 12 and a recovery flow passage 24 connected tothe liquid recovery port 22 are formed in the nozzle member 70. Theother end of the supply tube 13 is connected to the supply flow passage14, and the other end of the recovery tube 23 is connected to therecovery flow passage 24. The liquid supply port 12, the supply flowpassage 14, and the supply tube 13 construct parts of the liquid supplymechanism 10. The liquid recovery port 22, the recovery flow passage 24,and the recovery tube 23 construct parts of the liquid recoverymechanism 20.

The liquid supply port 12 is provided opposite to the surface of thesubstrate P over the substrate P supported by the substrate stage PST.The liquid supply port 12 is separated from the surface of the substrateP by a predetermined distance. The liquid supply port 12 is arranged tosurround the projection area AR1 of the projection optical system PLonto which the exposure light beam EL is radiated. In this embodiment,the liquid supply port 12 is formed to have an annular slit-shaped formon the lower surface of the nozzle member 70 so that the projection areaAR1 is surrounded thereby. In this embodiment, the projection area AR1is set to have a rectangular shape in which the Y axis direction(non-scanning direction) is the longitudinal direction.

The supply flow passage 14 includes a buffer flow passage portion 14Hwhich has a part or portion connected to the other end of the supplytube 13, and an inclined flow passage portion 14S which has an upper endconnected to the buffer flow passage portion 14H and which has a lowerend connected to the liquid supply port 12. The inclined flow passageportion 14S has a shape corresponding to the liquid supply port 12. Theinclined flow passage portion 14S has a cross section which is takenalong the XY plane and which is formed to have an annular slit-shapedform to surround the optical element LS1. The inclined flow passageportion 14S has an angle of inclination corresponding to the sidesurface of the optical element LS1 arranged at the inside thereof. Theinclined flow passage portion 14S is formed so that the distance fromthe surface of the substrate P is increased at positions separatedfarther from the optical axis AX of the projection optical system PL(optical element LS1) as viewed in a side sectional view.

The buffer flow passage portion 14H is provided outside the inclinedflow passage portion 14S to surround the upper end of the inclined flowpassage portion 14S. The buffer flow passage portion 14H is the spaceportion which is formed to expand in the XY direction (horizontaldirection). The inner side of the buffer flow passage portion 14H (onthe side of the optical axis AX) is connected to the upper end of theinclined flow passage portion 14S. A connecting portion therebetweenforms a bent corner portion 17. A bank 15, which is formed to surroundthe upper end of the inclined flow passage portion 14S, is provided inthe vicinity of the connecting portion (bent corner portion) 17,specifically in an area disposed at the inside of the buffer flowpassage portion 14H (on the side of the optical axis AX). The bank 15 isprovided to protrude in the +Z direction from the bottom surface of thebuffer flow passage portion 14H. A narrow flow passage portion 14N,which is narrower than the buffer flow passage portion 14H, is formed bythe bank 15.

In this embodiment, the nozzle member 70 is formed by combining a firstmember 71 and a second member 72. Each of the first and second members71, 72 can be formed of, for example, aluminum, titanium, stainlesssteel, duralumin, or any alloy containing at least two of them.

The first member 71 includes a side plate portion 71A, a ceiling plateportion 71B which has an outer end connected to an upper predeterminedposition of the side plate portion 71A, an inclined plate portion 71Cwhich has an upper end connected to an inner end of the ceiling plateportion 71B, and a bottom plate portion 71D which is connected to alower end of the inclined plate portion 71C (see FIG. 3). The respectiveplate portions are joined to one another and formed as an integratedbody. The second member 72 includes a ceiling plate portion 72B whichhas an outer end connected to an upper end of the first member 71, aninclined plate portion 72C which has an upper end connected to an innerend of the ceiling plate portion 72B, and a bottom plate portion 72Dwhich is connected to a lower end of the inclined plate portion 72C. Therespective plate portions are joined to one another and formed as anintegrated body. The bottom surface of the buffer flow passage portion14H is formed by the ceiling plate portion 71B of the first member 71.The ceiling surface of the buffer flow passage portion 14H is formed bythe lower surface of the ceiling plate portion 72B of the second member72. The bottom surface of the inclined flow passage portion 14S isformed by the upper surface (surface directed to the side of the opticalelement LS1) of the inclined plate portion 71C of the first member 71.The ceiling surface of the inclined flow passage portion 14S is formedby the lower surface (surface directed to the side opposite to theoptical element LS1) of the inclined plate portion 72C of the secondmember 72. Each of the inclined plate portion 71C of the first member 71and the inclined plate portion 72C of the second member 72 is formed tohave a mortar-shaped form. The slit-shaped supply flow passage 14 isformed by combining the first and second members 71, 72. The outer sideof the buffer flow passage portion 14H is closed by the upper area ofthe side plate portion 71A of the first member 71. The upper surface ofthe inclined plate portion 72C of the second member 72 is opposed to theside surface of the optical element LS1.

The liquid recovery port 22 is provided opposite to the surface of thesubstrate P over or above the substrate P supported by the substratestage PST. The liquid recovery port 22 is separated from the surface ofthe substrate P by predetermined distances. The liquid recovery port 22is provided outside the liquid supply port 12 with respect to theprojection area AR1 of the projection optical system PL, while theliquid recovery port 22 is separated farther from the projection areaAR1 than the liquid supply port 12. The liquid recovery port 22 isformed to surround the liquid supply port 12 and the projection areaAR1. Specifically, a space 24, which is open downwardly, is formed bythe side plate portion 71A, the ceiling plate portion 71B, and theinclined plate portion 71C of the first member 71. The liquid recoveryport 22 is formed by the opening of the space 24. The recovery flowpassage 24 is formed by the space 24. The other end of the recovery tube23 is connected to a part of the recovery flow passage (space) 24.

A porous member 25, which has a plurality of holes, is arranged for theliquid recovery port 22 to cover the liquid recovery port 22 therewith.The porous member 25 is formed of a mesh member having a plurality ofholes. The porous member 25 may be formed of, for example, a mesh memberformed with a honeycomb pattern including a plurality of substantiallyhexagonal holes. The porous member 25 is formed to have a thinplate-shaped form. The porous member 25 has, for example, a thickness ofabout 100 μm.

The porous member 25 can be formed, for example, such that the punchingor boring processing is performed for a plate member as a base materialfor the porous member made of, for example, stainless steel (forexample, SUS 316). A plurality of thin plate-shaped porous members 25may be arranged while being stuck in the liquid recovery port 22. It isalso allowable to perform, for the porous member 25, a surface treatmentto suppress the elution of any impurity to the liquid LQ or a surfacetreatment to enhance the liquid-attractive property. Such a surfacetreatment is exemplified by a treatment to adhere chromium oxide to theporous member 25, including, for example, the “GOLDEP” treatment or the“GOLDEP WHITE” treatment available from Kobelco Eco-Solutions Co., Ltd.When the surface treatment is performed as described above, it ispossible to avoid the inconvenience which would be otherwise caused, forexample, such that the impurity is eluted from the porous member 25 tothe liquid LQ. The surface treatment as described above may be alsoperformed for the nozzle member 70 (first and second members 71, 72).The porous member 25 may be formed of a material (for example, titanium)in which the impurity is scarcely eluted to the liquid LQ.

The nozzle member 70 is rectangular as viewed in a plan view. As shownin FIG. 3, the liquid recovery port 22 is formed to be frame-shaped(having a shape of “□” (rectangle) or square frame-shaped) as viewed ina plan view to surround the projection area AR1 and the liquid supplyport 12 on the lower surface of the nozzle member 70. The thinplate-shaped porous member 25 is arranged in the liquid recovery port22. The bottom plate portion 71D of the first member 71 is arrangedbetween the liquid recovery port 22 (porous members 25) and the liquidsupply port 12. The liquid supply port 12 is formed to have an annularslit-shaped form as viewed in a plan view between the bottom plateportion 71D of the first member 71 and the bottom plate portion 72D ofthe second member 72.

Each of the surfaces (lower surfaces) of the bottom plate portions 71D,72D of the nozzle member 70, which is opposed to the substrate P, is aflat surface which is parallel to the XY plane. That is, the nozzlemember 70 is provided with the bottom plate portions 71D, 72D having thelower surfaces which are formed to be opposed to the surface of thesubstrate P (XY plane) supported by the substrate stage PST and whichare formed to be substantially parallel to the surface of the substrateP. In this embodiment, the lower surface of the bottom plate portion 71Dis substantially flush with the lower surface of the bottom plateportion 72D to form a portion at which the gap is the smallest withrespect to the surface of the substrate P arranged on the substratestage PST. Accordingly, it is possible to form the liquid immersion areaAR2 by satisfactorily retaining the liquid LQ between the substrate Pand the lower surfaces of the bottom plate portions 71D, 72D. In thefollowing description, the lower surfaces (flat portions) of the bottomplate portions 71D, 72D, which are formed to be opposed to the surfaceof the substrate P and substantially parallel to the surface of thesubstrate P (XY plane), will be appropriately referred to as “landsurface 75” in combination.

The land surface 75 is a surface which is included in the nozzle member70 and which is arranged at the position nearest to the substrate Psupported by the substrate stage PST. In this embodiment, the lowersurface of the bottom plate portion 71D is substantially flush with thelower surface of the bottom plate portion 72D. Therefore, the lowersurface of the bottom plate portion 71D and the lower surface of thebottom plate portion 72D are referred to as “land surface 75” incombination. However, the porous member 25 may be also arranged on theportion at which the bottom plate portion 71D is arranged to use as theliquid recovery port. In this case, only the lower surface of the bottomplate portion 72D is the land surface 75.

The porous member 25 has lower surfaces 2 which are opposed to thesubstrate P supported by the substrate stage PST. The porous member 25is provided in the liquid recovery port 22 so that the lower surfaces 2are inclined with respect to the surface of the substrate P (i.e., theXY plane) supported by the substrate stage PST. That is, the porousmember 25, which is provided in the liquid recovery port 22, haveinclined surfaces (lower surfaces) 2 which are opposed to the surface ofthe substrate P supported by the substrate stage PST. The liquid LQ isrecovered via the inclined surfaces 2 of the porous member 25 arrangedin the liquid recovery port 22. Therefore, the liquid recovery port 22is formed on the inclined surfaces 2. In other words, the entireinclined surfaces function as the liquid recovery port 22 in thisembodiment. The liquid recovery port 22 is formed to surround theprojection area AR1 onto which the exposure light beam EL is radiated.Therefore, the inclined surfaces 2 of the porous member 25 arranged inthe liquid recovery port 22 are formed to surround the projection areaAR1.

Each of the inclined surface 2 of the porous member 25 opposed to thesubstrate P is formed such that the distance with respect to the surfaceof the substrate P is increased at positions separated farther from theoptical axis AX of the projection optical system PL (optical elementLS1). As shown in FIG. 3, the liquid recovery port 22 is formed to havethe shape of “□” (rectangle) or square frame-shaped form as viewed in aplan view in this embodiment. The porous member 25 includes four porousmembers 25A to 25D which are arranged in combination in the liquidrecovery port 22. In particular, the porous members 25A, 25C, which arearranged on the both sides, respectively, in the X axis direction(scanning direction) with respect to the projection area AR1, arearranged so that the distances with respect to the surface of thesubstrate P are increased at positions separated farther from theoptical axis AX while the surfaces thereof are perpendicular to the XZplane. Further, the porous members 25B, 25D, which are arranged on theboth sides, respectively, in the Y axis direction with respect to theprojection area AR1, are arranged so that the distances with respect tothe surface of the substrate P are increased at positions separatedfarther from the optical axis AX while the surfaces thereof areperpendicular to the YZ plane.

The angle of inclination of the lower surface 2 of the porous member 25with respect to the XY plane is set between 3 and 20 degrees inconsideration of, for example, the viscosity of the liquid LQ and thecontact angle of the liquid LQ on the surface of the substrate P. Inthis embodiment, the angle of inclination is set to 7 degrees.

The lower end of the side plate portion 71A is provided at approximatelythe same position (height) in the Z axis direction as that of the lowersurface of the bottom plate portion 71D connected to the lower end ofthe inclined plate portion 71C of the first member. The porous member 25is attached to the liquid recovery port 22 of the nozzle member 70 sothat the inner edge portion of the inclined surface 2 has approximatelythe same height as that of the lower surface (land surface 75) of thebottom plate portion 71D, and the inner edge portion of the inclinedsurface 2 is continued to the lower surface (land surface 75) of thebottom plate portion 71D. That is, the land surface 75 is formedcontinuously to the inclined surfaces 2 of the porous members 25. Theporous members 25 are arranged so that the distances with respect to thesurface of the substrate P are increased at positions separated fartherfrom the optical axis AX. Wall portions 76, which are formed by apartial area of the lower portion of the side plate portion 71A, areprovided outside the outer edge of the inclined surface 2 (porous member25). The wall portions 76 are provided at the circumferential edges ofthe porous members 25 (inclined surfaces 2) so that the porous members25 (inclined surfaces 2) are surrounded thereby. The wall portions 76are provided outside the liquid recovery port 22 with respect to theprojection area AR1 in order to suppress the leakage of the liquid LQ.

A portion of the bottom plate portion 72D, which forms the land surface75, is arranged between the substrate P and the end surface (lowersurface) T1 disposed on the side of the image plane of the opticalelement LS1 of the projection optical system PL in relation to the Zaxis direction. That is, a portion of the land surface 75 enters thespace disposed under or below the lower surface (end surface) T1 of theoptical element LS1 of the projection optical system PL. An opening 74,through which the exposure light beam EL passes, is formed at a centralportion of the bottom plate portion 72D which forms the land surface 75.The opening 74 has a shape corresponding to the projection area AR1. Inthis embodiment, the opening 74 is formed to have an elliptical shape inwhich the Y axis direction (non-scanning direction) is the longitudinaldirection. The opening 74 is formed to be larger than the projectionarea AR1. The exposure light beam EL, which is allowed to pass via theprojection optical system PL, can arrive at the surface of the substrateP without being shielded by the bottom plate portion 72D. That is, atleast a portion of the land surface 75 is arranged at the position atwhich the optical path for the exposure light beam EL is not inhibitedso that the optical path for the exposure light beam EL is surroundedand the portion of the land surface 75 enters the space disposed underor below the end surface T1 of the projection optical system PL. Inother words, at least a portion of the land surface 75 is arranged tosurround the projection area AR1 between the substrate P and the endsurface T1 disposed on the side of the image plane of the projectionoptical system PL. The bottom plate portion 72D is arranged opposite tothe surface of the substrate P with the lower surface thereof being theland surface 75. The bottom plate portion 72D is provided to make nocontact with the substrate P and the lower surface T1 of the opticalelement LS1. The edge portion 74E of the opening 74 may be formed to berectangular, acute angular, or circular arc-shaped.

The land surface 75 is arranged between the projection area AR1 and theinclined surfaces 2 of the porous member 25 arranged in the liquidrecovery port 22. The liquid recovery port 22 is arranged to surroundthe land surface 75 outside the land surface 75 with respect to theprojection area AR1. That is, the liquid recovery port 22 is arranged tosurround the land surface at the position separated farther from theoptical path for the exposure light beam EL than the land surface 75.The liquid supply port 12 is also arranged outside the land surface 75with respect to the projection area AR1. The liquid supply port 12 isprovided between the liquid recovery port 22 and the projection area AR1of the projection optical system PL. The liquid LQ, which is fed to formthe liquid immersion area AR2, is supplied between the liquid recoveryport 22 and the projection area AR1 of the projection optical system PLvia the liquid supply port 12. The number, the position, and the shapeof each of the liquid supply port 12 and the liquid recovery port 22 arenot limited to those described in the embodiment of the presentinvention. It is enough to adopt such an arrangement that the liquidimmersion area AR2 can be maintained in a desired state. For example,the liquid recovery port 22 may be arranged so that the land surface 75is not surrounded thereby. In this case, it is also allowable that theliquid recovery port 22 is provided in only predetermined areas disposedon the both sides in the scanning direction (X direction) with respectto the projection area AR1, or the liquid recovery port 22 is providedin only predetermined areas disposed on the both sides in thenon-scanning direction (Y direction) with respect to the projection areaAR1.

As described above, the land surface 75 is arranged between thesubstrate P and the lower surface T1 of the optical element LS1. Thedistance between the surface of the substrate P and the lower surface T1of the optical element LS1 is longer than the distance between thesurface of the substrate P and the land surface 75. That is, the lowersurface T1 of the optical element LS1 is formed at the position higherthan that of the land surface 75 (so that the position is separatedfarther from the substrate P). In this embodiment, the distance betweenthe substrate P and the lower surface T1 of the optical element LS1 isabout 3 mm, and the distance between the land surface 75 and thesubstrate P is about 1 mm. The liquid LQ of the liquid immersion areaAR2 makes contact with the land surface 75, and the liquid LQ of theliquid immersion area AR2 also makes contact with the lower surface T1of the optical element LS1. That is, the land surface 75 and the lowersurface T1 serve as the liquid contact surfaces which make contact withthe liquid LQ of the liquid immersion area AR2.

The liquid contact surface T1 of the optical element LS1 of theprojection optical system PL has the liquid-attractive property orlyophilicity (water-attractive property or hydrophilicity). In thisembodiment, the liquid-attracting treatment is performed for the liquidcontact surface T1. The liquid contact surface T1 of the optical elementLS1 is liquid-attractive or lyophilic owing to the liquid-attractingtreatment. The land surface 75 is also subjected to theliquid-attracting treatment to have the lyophilicity. A portion (forexample, the lower surface of the bottom plate portion 71D) of the landsurface 75 may be subjected to the liquid-repelling treatment to havethe liquid repellence. Of course, as described above, each of the firstmember 71 and the second member 72 may be formed of a lyophilic materialto allow the land surface 75 to have the lyophilicity.

Those adoptable as the liquid-attracting treatment to provide thelyophilicity for the predetermined member such as the liquid contactsurface T1 of the optical element LS1 include, for example, a treatmentin which a liquid-attractive material such as MgF₂, Al₂O₃, or SiO₂ isadhered. Alternatively, the lyophilicity (hydrophilicity) can be alsoapplied or added by forming a thin film with a substance having amolecular structure with large polarity accompanied with the OH groupsuch as alcohol, as the liquid-attracting treatment (water-attractingtreatment), because the liquid LQ in this embodiment is water having thelarge polarity. When the optical element LS1 is formed of calciumfluorite or silica glass, it is possible to obtain a satisfactoryliquid-attractive property even when no liquid-attracting treatment isperformed, because the calcium fluorite and the silica glass have thelarge affinities for water. Thus, it is possible to allow the liquid LQto make tight contact with the substantially entire surface of theliquid contact surface (end surface) T1 of the optical element LS1.

The liquid-repelling treatment, which is adopted when a portion of theland surface 75 is allowed to have the liquid repellence, includes, forexample, a treatment in which a liquid-repellent material including, forexample, fluorine-based material such as polytetrafluoroethylene (Teflon(trade name)), acrylic resin material, or silicon-based resin materialis adhered. When the upper surface 91 of the substrate stage PST isallowed to have the liquid repellence, then it is possible to suppressthe outflow of the liquid LQ to the outside of the substrate P (outsideof the upper surface 91) during the liquid immersion exposure, it ispossible to smoothly recover the liquid LQ after the liquid immersionexposure as well, and it is possible to avoid the inconvenience whichwould be otherwise caused such that the liquid LQ remains on the uppersurface 91.

In order to supply the liquid LQ onto the substrate P, the control unitCONT drives the liquid supply section 11 to feed the liquid LQ from theliquid supply section 11. The liquid LQ, fed from the liquid supplysection 11, is allowed to flow through the supply tube 13, and then theliquid LQ flows into the buffer flow passage portion 14H of the supplyflow passage 14 of the nozzle member 70. The buffer flow passage portion14H is the space portion which is expanded in the horizontal direction.The liquid LQ, which has flown into the buffer flow passage portion 14H,is allowed to flow while being spread in the horizontal direction. Thebank 15 is formed in the area disposed on the inner side (side of theoptical axis AX) which is the downstream side of the flow passage of thebuffer flow passage portion 14H. Therefore, the liquid LQ is spread overthe entire region of the buffer flow passage portion 14H, and then theliquid LQ is once stored. After the liquid LQ is stored in not less thana predetermined amount in the buffer flow passage portion 14H (after theliquid level of the liquid LQ is not less than the height of the bank15), the liquid LQ is allowed to flow into the inclined flow passageportion 14S via the narrow flow passage portion 14N. The liquid LQ,which has flown into the inclined flow passage portion 14S, is allowedto flow downwardly along the inclined flow passage portion 14S. Then,the liquid LQ is supplied from the liquid supply port 12 onto thesubstrate P which is arranged on the side of the image plane of theprojection optical system PL. The liquid supply port 12 supplies theliquid LQ onto the substrate P from the position over or above thesubstrate P.

When the bank 15 is provided as described above, the liquid LQ, whichoutflows from the buffer flow passage portion 14H, is supplied onto thesubstrate P substantially uniformly from the entire region of the liquidsupply port 12 which is formed annularly to surround the projection areaAR1. In other words, if the bank 15 (narrow flow passage portion 14N) isnot formed, the flow rate of the liquid LQ allowed to flow through theinclined flow passage portion 14S is larger in the area disposed in thevicinity of the connecting portion between the supply tube 13 and thebuffer flow passage portion 14H than in other areas. Therefore, theamount of the liquid to be supplied to the surface of the substrate P issometimes nonuniform at respective positions of the liquid supply port12 which is formed annularly. However, the narrow flow passage portion14N is provided to form the buffer flow passage portion 14H. The liquidsupply is started for the liquid supply port 12 after the liquid LQ ofnot less than the predetermined amount is stored in the buffer flowpassage portion 14H. Therefore, the liquid LQ can be supplied onto thesubstrate P in a state in which the flow rate distribution and the flowvelocity distribution are uniformized at respective positions of theliquid supply port 12. The bubble tends to remain, for example, upon thestart of the supply in the vicinity of the bent corner portion 17 of thesupply flow passage 14. However, the supply flow passage 14, which isdisposed in the vicinity of the bent corner portion 17, is narrowed toform the narrow flow passage portion 14N. Accordingly, the high velocityis realized for the flow rate of the liquid LQ allowed to flow throughthe narrow flow passage portion 14N. The flow of the liquid LQ allowedto have the high velocity can be used to discharge (purge) the bubble tothe outside of the supply flow passage 14 via the liquid supply port 12.When the liquid immersion exposure operation is executed afterdischarging the bubble, the exposure process can be performed in thestate in which no bubble is present in the liquid immersion area AR2.The bank 15 may be provided to protrude in the −Z direction from theceiling surface of the buffer flow passage 14H. In principle, it isenough that the narrow flow passage portion 14N, which is narrower thanthe buffer flow passage portion 14H, is provided on the downstream sideof the flow passage as compared with the buffer flow passage portion14H.

The bank 15 may be made partially low (high). When an area, in which theheight differs, is partially provided for the bank 15, it is possible toprevent the gas (bubble) from remaining in the liquid for forming theliquid immersion area AR2 when the supply of the liquid LQ is started.The buffer flow passage portion 14H may be divided into a plurality offlow passages so that the liquid LQ can be supplied in different amountsdepending on positions at the slit-shaped liquid supply port 12.

In order to recover the liquid LQ on the substrate P, the control unitCONT drives the liquid recovery section 21. When the liquid recoverysection 21, which has the vacuum system, is driven, the liquid LQ, whichis on the substrate P, is allowed to flow into the recovery flow passage24 via the liquid recovery port 22 arranged with the porous member 25.When the liquid LQ of the liquid immersion area AR2 is recovered, thelower surfaces (inclined surfaces) 2 of the porous member 25 makecontact with the liquid LQ. The liquid recovery port 22 (porous member25) is provided opposite to the substrate P over or above the substrateP. Therefore, the liquid LQ on the substrate P is recovered from thepositions above or over the substrate P. The liquid LQ, which is allowedto flow into the recovery flow passage 24, is allowed to flow throughthe recovery tube 23, and then the liquid LQ is recovered by the liquidrecovery section 21.

FIG. 5 shows an example of the liquid recovery section 21. Withreference to FIG. 5, the liquid recovery section 21 includes a recoverytank 26 which is connected to one end of the recovery tube 23, a vacuumpump (vacuum system) 27 which is connected to the recovery tank 26 via apiping 27K, a liquid discharge pump (water discharge pump) 29 which isconnected to the recovery tank 26 via a piping 29K, and a liquid levelsensor (water level sensor) 28 which is provided inside the recoverytank 26. One end of the recovery tube 23 is connected to an upperportion of the recovery tank 26. The piping 27K, which has one endconnected to the vacuum pump 27, has the other end connected to an upperportion of the recovery tank 26. The piping 29K, which has one endconnected to the liquid discharge pump 29, has the other end connectedto a lower portion of the recovery tank 26. When the vacuum pump 27 isdriven, then the liquid LQ is recovered via the liquid recovery port 22of the nozzle member 70, and the liquid LQ is accommodated in therecovery tank 26. When the liquid discharge pump 29 is driven, theliquid LQ, which is accommodated in the recovery tank 26, is dischargedto the outside via the piping 29K. The operations of the vacuum pump 26and the liquid discharge pump 29 are controlled by the control unitCONT. The liquid level sensor 28 measures the liquid level (water level)of the liquid LQ accommodated in the recovery tank 26. The measurementresult thereof is outputted to the control unit CONT. The control unitCONT adjusts the suction force (water discharge force) of the liquiddischarge pump 29 on the basis of the output of the liquid level sensor28 so that the liquid level (water level) of the liquid LQ accommodatedin the recovery tank 26 is substantially constant. The control unit CONTcan maintain a substantially constant liquid level of the liquid LQaccommodated in the recovery tank 26. Therefore, it is possible tostabilize the pressure in the recovery tank 26. Therefore, it ispossible to stabilize the recovery force (suction force) for the liquidLQ via the liquid recovery port 22. A liquid discharge valve may beprovided in place of the liquid discharge pump 29 in the embodimentshown in FIG. 5. For example, the open/closed state of the liquiddischarge valve may be adjusted, or the diameter of the discharge portmay be adjusted on the basis of the output of the liquid level sensor 28so that a substantially constant liquid level of the liquid LQ may bemaintained in the recovery tank 26.

An explanation will be made about an example of the recovery methodusing the liquid recovery mechanism 20 in this embodiment. This recoverymethod is referred to as “bubble point method” in this embodiment. Theliquid recovery mechanism 20 recovers only the liquid LQ from therecovery port 22 by using the bubble point method. Accordingly, it ispossible to suppress the occurrence of the vibration which would beotherwise caused by the recovery of the liquid.

An explanation will be made below about the principle of the liquidrecovery operation to be performed by the liquid recovery mechanism 20in this embodiment with reference to FIG. 6. The porous member 25 isarranged in the recovery port 22 of the liquid recovery mechanism 20.For example, a thin plate-shaped mesh member, in which a large number ofholes are formed, can be used as the porous member 25. In the bubblepoint method, only the liquid LQ is recovered from the holes of theporous member 25 by controlling the difference in pressure between theupper surface and the lower surface of the porous member 25 so that apredetermined condition is satisfied as described later on in a state inwhich the porous member 25 is wet. Parameters concerning the conditionof the bubble point include, for example, the pore size of the porousmember 25, the contact angle (affinity) of the porous member 25 withrespect to the liquid LQ, and the suction force of the liquid recoverysection 21 (pressure on the upper surface of the porous member 25).

FIG. 6 shows a magnified view illustrating a partial cross section ofthe porous member 25, which illustrates a specified example of theliquid recovery performed by the aid of the porous member 25. Thesubstrate P is arranged under or below the porous member 25. The gasspace and the liquid space are formed between the porous member 25 andthe substrate P. More specifically, the gas space is formed between afirst hole 25Ha of the porous member 25 and the substrate P, and theliquid space is formed between a second hole 25Hb of the porous member25 and the substrate P. Such a situation arises, for example, at the endof the liquid immersion area AR2 shown in FIG. 4. Such a situation mayalso arise when any liquid void is formed in the liquid LQ of the liquidimmersion area AR2. The flow passage space, which forms a part of therecovery flow passage 24, is formed over or above the porous member 25.

With reference to FIG. 6, it is assumed that the following conditionholds:

(4×γ×cos θ)/d≧(Pa−Pb)  (1A)

wherein Pa represents the pressure in the space between the substrate Pand the first hole 25Ha of the porous member 25 (pressure on the lowersurface of the porous member 25H), Pb represents the pressure in theflow passage space over or above the porous member 25 (pressure on theupper surface of the porous member 25), d represents the pore size(diameter) of the holes 25Ha, 25Hb, θ represents the contact angle ofthe porous member 25 (inside the hole 25H) with respect to the liquidLQ, and γ represents the surface tension of the liquid LQ. On thisassumption, as shown in FIG. 6, even when the gas space is formed on thelower side (side of the substrate P) of the first hole 25Ha of theporous member 25, it is possible to prevent the gas contained or presentin the space disposed under or below the porous member 25 from makingthe movement (inflow) into the space disposed over or above the porousmember 25 via the hole 25Ha. That is, when the contact angle θ, the poresize d, the surface tension γ of the liquid LQ, and the pressures Pa, Pbare optimized so that the condition of the expression (1A) is satisfied,then the interface between the liquid LQ and the gas is maintained inthe hole 25Ha of the porous member 25, and it is possible to suppressthe inflow of the gas from the first hole 25Ha. On the other hand, theliquid space is formed under (on the side of the substrate P) the secondhole 25Hb of the porous member 25. Therefore, it is possible to recoveronly the liquid LQ via the second hole 25Hb.

The hydrostatic pressure of the liquid LQ on the porous member 25 is notconsidered in the condition of the expression (1A) in order to simplifythe explanation.

In this embodiment, the liquid recovery mechanism 20 adjusts thepressure of the flow passage space over or above the porous member 25 sothat the expression (1A) is satisfied by controlling the suction forceof the liquid recovery section 21 while the pressure Pa of the spaceunder or below the porous member 25, the diameter d of the hole 25H, thecontact angle θ of the porous member 25 (inner surface of the hole 25H)with respect to the liquid LQ, and the surface tension γ of the liquid(pure water) LQ are constant. However, as (Pa−Pb) is larger in theexpression (1A), i.e., ((4×γ×cos θ)/d) is larger, the pressure Pb iscontrolled more easily so as to satisfy the expression (1A). Therefore,it is desirable that the diameter d of the holes 25Ha, 25Hb and thecontact angle θ of the porous member 25 with respect to the liquid LQare decreased to be as small as possible.

Next, an explanation will be made about a method for exposing thesubstrate P with the image of the pattern of the mask M by using theexposure apparatus EX constructed as described above.

The control unit CONT forms the liquid immersion area AR2 of the liquidLQ on the substrate P by supplying a predetermined amount of the liquidLQ onto the substrate P and recovering a predetermined amount of theliquid LQ on the substrate P by using the liquid immersion mechanism 1provided with the liquid supply mechanism 10 and the liquid recoverymechanism 20. The liquid LQ, which is supplied from the liquid immersionmechanism 1, forms the liquid immersion area AR2 locally on a part ofthe substrate P including the projection area AR1, the liquid immersionarea AR2 being larger than the projection area AR1 and smaller than thesubstrate P.

The control unit CONT recovers the liquid LQ on the substrate P by theliquid recovery mechanism 20 concurrently with the supply of the liquidLQ onto the substrate P by the liquid supply mechanism 10, while theimage of the pattern of the mask M is projected onto the substrate P sothat the exposure is performed via the projection optical system PL andthe liquid LQ between the projection optical system PL and the substrateP, while moving the substrate stage PST for supporting the substrate Pin the X axis direction (scanning direction).

The exposure apparatus EX of the embodiment of the present inventionperforms the projection exposure for the substrate P with the image ofthe pattern of the mask M while moving the mask M and the substrate P inthe X axis direction (scanning direction). During the scanning exposure,a part of the image of the pattern of the mask M is projected onto theprojection area AR1 via the projection optical system PL and the liquidLQ of the liquid immersion area AR2. The mask M is moved at the velocityV in the −X direction (or in the +X direction), in synchronization withwhich the substrate P is moved at the velocity β·V (β represents theprojection magnification) in the +X direction (or in the −X direction)with respect to the projection area AR1. A plurality of shot areas areset on the substrate P. After the exposure is completed for one shotarea, the next shot area is moved to the scanning start position inaccordance with the stepping movement of the substrate P. The scanningexposure process is successively performed thereafter for the respectiveshot areas while moving the substrate P in the step-and-scan manner.

In this embodiment, the porous member 25 is inclined with respect to thesurface of the substrate P. In this case, the liquid LQ is recoveredthrough the inclined surface 2 of the porous member 25 arranged in theliquid recovery port 22. The liquid LQ is recovered via the liquidrecovery port 22 including the inclined surface 2. The land surface 75(lower surface of the bottom plate portion 71D) is formed continuouslyto the inclined surface 2. In this case, when the substrate P issubjected to the scanning movement at a predetermined velocity by apredetermined distance in the +X direction with respect to the liquidimmersion area AR2 starting from the initial state shown in FIG. 7(a)(state in which the liquid immersion area AR2 of the liquid LQ is formedbetween the land surface 75 and the substrate P), a state as shown inFIG. 7(b) is given. In the predetermined state after the scanningmovement as shown in FIG. 7(b), a component F1 which moves obliquelyupwardly along the inclined surface 2 and a component F2 which moves inthe horizontal direction are generated in the liquid LQ of the liquidimmersion area AR2. In this case, the shape is maintained for aninterface (gas-liquid interface) LG between the liquid LQ of the liquidimmersion area AR2 and the space disposed outside thereof. Even when thesubstrate P is moved at a high velocity with respect to the liquidimmersion area AR2, it is possible to suppress any great change of theshape of the interface LG.

The distance between the inclined surface 2 and the substrate P islarger than the distance between the land surface 75 and the substrateP. That is, the space between the inclined surface 2 and the substrate Pis larger than the space between the land surface 75 and the substrateP. Therefore, when the substrate P is moved, it is possible to provide arelatively small distance L between an interface LG′ formed in theinitial state shown in FIG. 7(a) and the interface LG formed in thepredetermined state after the scanning movement shown in FIG. 7(b).Therefore, it is possible to suppress the spread or expansion of theliquid immersion area AR2, and it is possible to decrease the size ofthe liquid immersion area AR2.

For example, as shown in FIG. 8(a), even when the land surface 75 isformed continuously to a lower surface 2′ of the porous member 25arranged in the liquid recovery port 22, the lower surface 2′ of theporous member 25 is not inclined with respect to the substrate P, andthe lower surface 2′ of the porous member 25 is substantially parallelto the surface of the substrate P, in other words, even when the liquidrecovery port 22 including the lower surface 2′ is not inclined, thenthe shape of the interface LG is maintained when the substrate P ismoved with respect to the liquid immersion area AR2. However, only thecomponent F2 which moves in the horizontal direction is generated in theliquid LQ, and the component (F1) which moves upwardly is scarcelygenerated, because the lower surface 2′ is not inclined. In this case,the interface LG is moved by approximately the same distance as theamount of movement of the substrate P. Therefore, the distance L,between the interface LG′ in the initial state and the interface LG inthe predetermined state after the scanning movement, has a relativelylarge value, and the liquid immersion area AR2 is also increased inaccordance therewith. In such a circumstance, it is necessary to providea large size of the nozzle member 70 as well in response to the largeliquid immersion area AR2. Further, it is also necessary to increase thesize of the substrate stage PST itself and the movement stroke of thesubstrate stage PST in response to the size of the liquid immersion areaAR2, resulting in the entire exposure apparatus EX having a huge size.The increase in the size of the liquid immersion area AR2 is conspicuousas the scanning velocity of the substrate P with respect to the liquidimmersion area AR2 is increased to be high.

On the other hand, as shown in FIG. 8(b), when the distance between thelower surface 2′ and the substrate P is made larger than the distancebetween the land surface 75 and the substrate P by providing adifference in height between the land surface 75 and the liquid recoveryport 22 (lower surface 2′ of the porous member 25), in other words, whenthe space between the lower surface 2′ and the substrate P is madelarger than the space between the land surface 75 and the substrate P,then the component F1′ which moves upwardly is generated in the liquidLQ. Therefore, it is possible to provide a relatively small value of thedistance L, and it is possible to suppress the increase in the size ofthe liquid immersion area AR2. However, the difference in height isprovided between the land surface 75 and the lower surface 2′, and theland surface 75 is not formed continuously to the lower surface 2′.Therefore, the shape of the interface LG tends to be collapsed. If theshape of the interface LG is collapsed, there is such a high possibilitythat the following inconvenience may arise. That is, the gas is mixed inthe liquid LQ of the liquid immersion area AR2, and any bubble is formedin the liquid LQ. For example, when the substrate P is subjected to thescanning at a high velocity in the +X direction, if the difference inheight is present, then the shape of the interface LG is collapsed, thecomponent F1′ to cause the upward movement is further increased, and thefilm thickness of the liquid LQ is thinned in the area disposed on themost +X side of the liquid immersion area AR2. If the substrate P issubjected to the movement in the −X direction (reverse scanning) in thisstate, there is such a high possibility that the phenomenon of thebreakage of the liquid LQ may arise. If the broken liquid (see thereference numeral LQ′ in FIG. 8(b)) remains, for example, on thesubstrate P, an inconvenience occurs such that the adhesion trace(so-called water mark) is formed on the substrate due to thevaporization of the liquid LQ′. There is also such a high possibilitythat the liquid LQ may outflow to the outside of the substrate P, andthe inconvenience including, for example, the rust and the electricleakage may be caused on the peripheral members and/or the equipment.The possibility of the occurrence of the inconvenience as describedabove is increased as the scanning velocity of the substrate P withrespect to the liquid immersion area AR2 is increased to be high.

In this embodiment, the inclined surface 2 is formed continuously to theland surface 75 (lower surface of the bottom plate portion 71D), and theliquid recovery port 22 of the liquid immersion mechanism 1 (liquidrecovery mechanism 20) is formed on the inclined surface 2 opposite oropposed to the surface of the substrate P. Therefore, even when thesubstrate P and the liquid immersion area AR2 formed on the side of theimage plane of the projection optical system PL are relatively moved, itis possible to maintain the shape of the interface LG (decrease thechange of the shape of the interface LG), and it is possible to maintainthe desired state for the size and the shape of the liquid immersionarea AR2, while suppressing the distance of movement of the interface LGbetween the liquid LQ of the liquid immersion area AR2 and the spacedisposed outside thereof. Therefore, it is possible to avoid theinconvenience which would be otherwise caused, for example, such thatany bubble is formed in the liquid LQ, the liquid cannot be recoveredsufficiently, and/or the liquid outflows. Further, it is possible todecrease the size of the liquid immersion area AR2. Therefore, it ispossible to realize the compact size of the entire exposure apparatus EXas well.

When the substrate P is subjected to the high velocity scanning, thereis such a high possibility that the liquid LQ of the liquid immersionarea AR2 may outflow to the outside, and the liquid LQ of the liquidimmersion area AR2 may be scattered to the surroundings. However, it ispossible to suppress the leakage of the liquid LQ, because the wallportion 76 is provided at the circumferential edge of the inclinedsurface 2. That is, a buffer space is formed at the inside of the wallportion 76 by providing the wall portion 76 at the circumferential edgeof the porous member 25. Therefore, even when the liquid LQ arrives atthe inner side surface of the wall portion 76, the liquid LQ for formingthe liquid immersion area AR2 is spread to the buffer space disposed atthe inside of the wall portion 76 while causing the wetting. Therefore,it is possible to more reliably avoid the leakage of the liquid LQ tothe outside of the wall portion 76.

Further, the portion of the land surface 75 (lower surface of the bottomplate portion 72D) is arranged under or below the end surface T1 of theprojection optical system PL to surround the projection area AR1.Therefore, the small gap, which is formed between the portion of theland surface 75 (lower surface of the bottom plate portion 72D) and thesurface of the substrate P, is formed in the vicinity of the projectionarea to surround the projection area. Therefore, the small liquidimmersion area, which is necessary and sufficient to cover theprojection area AR1, can be continuously retained. Therefore, it ispossible to realize the compact size of the entire exposure apparatus EXwhile suppressing the inconvenience such as the outflow of the liquid LQand the entrance of the gas into the liquid LQ of the liquid immersionarea AR2 even when the substrate P is moved (scanned) at a highvelocity. Further, the liquid supply port 12 is arranged outside theportion of the land surface 75 (lower surface of the bottom plateportion 72D). Therefore, it is possible to avoid the entrance of the gas(bubble) into the liquid LQ for forming the liquid immersion area AR2.Even when the substrate P is moved at a high velocity, it is possible tocontinuously fill the optical path for the exposure light beam EL withthe liquid.

Second Embodiment

Next, a second embodiment of the present invention will be explainedwith reference to FIG. 9. In the following explanation, the constitutiveparts, which are the same as or equivalent to those of the embodimentdescribed above, are designated by the same reference numerals, and anyexplanation of which will be simplified or omitted. In the firstembodiment described above, the inclined surface 2 is formed byattaching the thin plate-shaped porous member 25 obliquely with respectto the substrate P. However, as shown in FIG. 9, an inclined surface 2″,for which the distance with respect to the surface of the substrate P isincreased at positions separated farther from the optical axis AX of theexposure light beam EL, may be provided on the lower surface of thenozzle member 70, and the liquid recovery port 22 may be formed at apredetermined position (in a predetermined area) of a part of theinclined surface 2″. The porous member 25 may be provided in the liquidrecovery port 22. In this case, the inclined surface 2″ of the nozzlemember 70 is continued to the lower surface 2 of the porous member 25,and the inclined surface 2″ is substantially flush with the lowersurface 2. Also in this case, for example, when the interface LG of theliquid LQ is formed between the inclined surface 2″ and the substrate P,then the shape of the interface LG can be maintained, and it is possibleto avoid the inconvenience which would be otherwise caused, for example,such that the any bubble is generated in the liquid LQ of the liquidimmersion area AR2. It is also possible to decrease the size of theliquid immersion area AR2.

Third Embodiment

FIG. 10 shows a third embodiment of the present invention. As shown inFIG. 10, a first area 2A, which is included in the lower surface 2 ofthe porous member 25 and which is disposed near to the optical axis AX,may be formed so that an angle of inclination of the first area 2A withrespect to the substrate P is larger than an angle of inclination of asecond area 2B with respect to the substrate P, the second area 2B beingdisposed outside the first area 2A.

Fourth Embodiment

FIG. 11 shows a fourth embodiment of the present invention. As shown inFIG. 11, a first area 2A, which is included in the lower surface 2 ofthe porous member 25 and which is disposed near to the optical axis AX,may be formed so that an angle of inclination of the first area 2A withrespect to the substrate P is smaller than an angle of inclination of asecond area 2B with respect to the substrate P, the second area 2B beingdisposed outside the first area 2A. That is, it is not necessarilyindispensable that the lower surface 2 of the porous member 25 is a flatsurface. It is enough that the lower surface 2 of the porous member 25is provided so that the distance with respect to the surface of thesubstrate P is increased at positions separated farther from the opticalaxis AX of the exposure light beam EL.

Fifth Embodiment

FIG. 12 shows a fifth embodiment of the present invention. As shown inFIG. 12, a plurality of fin members 150 may be formed on the inclinedsurfaces (lower surfaces of the porous members 25) formed on the lowersurface of the nozzle member 70. The fin member 150 is substantiallytriangular as viewed in a side view. With reference to the sidesectional view shown in FIG. 12, the fin members 150 are arranged in thebuffer space formed by the lower surface 2 of the porous members 25 atthe inside of the wall portions 76. The fin members 150 are attached tothe inner side surfaces 76 of the wall portions 76 radially so that thelongitudinal directions thereof are directed outwardly. In this case,the plurality of fin members 150 are separated and away from oneanother. Space portions are formed between the respective fin members150. When the plurality of fin members 150 are arranged as describedabove, it is possible to increase the liquid contact areas of theinclined surfaces (lower surfaces of the porous member 25) formed on thelower surface of the nozzle member 70. Therefore, it is possible toimprove the performance to retain the liquid LQ on the lower surface ofthe nozzle member 70. The plurality of fin members may be provided atequal intervals, or they may be provided at unequal intervals. Forexample, the distance between the fin members 150 arranged on the bothsides in the X axis direction with respect to the projection area AR1may be set to be smaller than the distance between the fin members 150arranged on the both sides in the Y axis direction with respect to theprojection area AR1. It is preferable that the surface of the fin member150 is liquid-attractive with respect to the liquid LQ. The fin member150 may be formed by performing the “GOLDEP” treatment or the “GOLDEPWHITE” treatment to stainless steel (for example, SUS316).Alternatively, the fin member 150 may be formed of, for example, glass(silica glass).

Sixth Embodiment

Next, a sixth embodiment of the present invention will be explained withreference to FIGS. 13, 14, 15, and 16. Mechanisms and members, which arethe same as or similar to those of the respective embodiments describedabove, are designated by common reference numerals, and any detailedexplanation of which will be omitted. FIG. 13 shows, with partialcutout, a schematic perspective view illustrating those disposed in thevicinity of a nozzle member 70′. FIG. 14 shows a perspective viewillustrating the nozzle member 70′ as viewed from the lower side. FIG.15 shows a side sectional view taken in parallel to the YZ plane. FIG.16 shows a side sectional view taken in parallel to the XZ plane.

The nozzle member 70′ of this embodiment is constructed by combining afirst member 171 and a second member 172. The nozzle member 70′ isformed to be substantially circular as a whole as viewed in a plan view.The first member 171 has a side plate portion 171A and a thick-walledinclined plate portion 171C. The upper end of the side plate portion171A is connected to the upper end of the inclined plate portion 171C.On the other hand, the second member 172 has an inclined plate portion172C and a bottom plate portion 172D which is connected to the lower endof the inclined plate portion 172C. Each of the inclined plate portion171C of the first member 171 and the inclined plate portion 172C of thesecond member 172 is formed to have a mortar-shaped form. The inclinedplate portion 172C of the second member 172 is arranged inside theinclined plate portion 171C of the first member 171. The first member171 and the second member 172 are supported by an unillustrated supportmechanism to provide such a state that the inner side surface 171T ofthe inclined plate portion 171C of the first member 171 is slightlyseparated from the outer side surface 172S of the inclined plate portion172C of the second member 172. A slit-shaped groove 73, which is annularas viewed in a plan view, is formed between the inner side surface 171Tof the inclined plate portion 171C of the first member 171 and the outerside surface 172S of the inclined plate portion 172C of the secondmember 172. In this embodiment, a slit width G1 of the groove 73 is setto be, for example, about 3 mm. In this embodiment, the groove 73 isformed to have an inclination of about 45 degrees with respect to the XYplane (surface of the substrate P).

The optical element LS1 is arranged inside a hole 70H defined by theinclined plate portion 172C of the second member 172. The side surfaceof the optical element LS1 arranged in the hole 70H is opposed to theinner side surface 172T of the inclined plate portion 172C of the secondmember 172. The inner side surface 172T of the inclined plate portion172C is liquid-repellent (water-repellent) with respect to the liquid LQto suppress the inflow of the liquid LQ into a gap between the sidesurface of the projection optical system PL and the inner side surface172T of the inclined plate portion 172C (nozzle member 70′).

A lower surface 171R of the inclined plate portion 171C of the firstmember 171, which is opposite to the substrate P, is a flat surfacewhich is parallel to the XY plane. The lower surface 172R of the bottomplate portion 172D of the second member 172, which is opposed or opposedto the substrate P, is also a flat surface which is parallel to the XYplane. The lower surface 171R of the inclined plate portion 171C of thefirst member 171 is substantially flush with the lower surface 172R ofthe bottom plate portion 172D of the second member 172. The land surface75 of the nozzle member 70′, which is opposite to the surface of thesubstrate P supported by the substrate stage PST (upper surface of thesubstrate stage PST) and which is disposed most closely to the surfaceof the substrate P (upper surface of the substrate stage PST), is formedby the lower surface 171R of the inclined plate portion 171 and thelower surface 172R of the bottom plate portion 172D. An opening 74,through which the exposure light beam EL is allowed to pass, is formedat a central portion of the bottom plate portion 172D which forms theland surface 75. That is, the land surface 75 is formed to surround theprojection area AR1.

As shown in FIG. 15, a portion of the bottom plate portion 172D forforming the land surface 75 is arranged between the substrate P(substrate stage PST) and the lower surface T1 on the side of the imageplane of the optical element LS1 of the projection optical system PL inrelation to the Z axis direction. The bottom plate portion 172D isprovided to make no contact with the lower surface T1 of the opticalelement LS1 and the substrate P (substrate stage PST). The upper surfaceof the bottom plate portion 172D is arranged so that the upper surfaceof the bottom plate portion 172D is opposite to the lower surface T1 ofthe optical element LS1 and the upper surface of the bottom plateportion 172D is substantially in parallel to the lower surface of theoptical element LS1. A predetermined gap (space) G2 is formed betweenthe end surface T1 of the projection optical system PL and the uppersurface of the bottom plate portion 172D.

A space 24, which is open downwardly, is formed for the first member171. The liquid recovery port 22 is formed at the opening of the space24 in the same manner as in the first embodiment described above. Thespace 24 functions as the recovery flow passage. The other end of therecovery tube 23 is connected to a portion of the recovery flow passage(space) 24. A porous member 25, which has a plurality of holes, isarranged in the liquid recovery port 22 to cover the liquid recoveryport 22. The porous member 25 has the lower surface 2 which is oppositeto the substrate P supported by the substrate stage PST. The porousmember 25 is provided in the liquid recovery port 22 so that the lowersurface 2 is inclined with respect to the surface of the substrate Psupported by the substrate stage PST (i.e., the XY plane) in the samemanner as in the first embodiment described above. The inclined surface2 of the porous member 25 is formed so that the distance with respect tothe surface of the substrate P is increased at positions separatedfarther from the optical axis AX of the projection optical system PL(optical element LS1). As shown in FIG. 15, the porous member 25 isattached to the liquid recovery port 22 of the nozzle member 70′ so thatthe inner edge portion of the inclined surface 2 has approximately thesame height as that of the lower surface 171R (land surface 75) of thefirst member 171, and the inner edge portion of the inclined surface 2is continued to the lower surface 171R (land surface 75).

As shown in FIG. 14, the liquid recovery port 22 is formed to be annularas viewed in a plan view on the lower surface of the nozzle member 70′to surround the opening 74 (projection area AR1), the groove 73, and theland surface 75. The land surface 75 is arranged between the opening 74through which the exposure light beam EL is allowed to pass (projectionarea AR1) and the inclined surface 2 of the porous member 25 arranged inthe liquid recovery port 22. The liquid recovery port 22 is arrangedoutside the land surface 75 with respect to the opening 74 (projectionarea AR1) to surround the land surface 75.

A plurality of fin members 150 are provided radially on the inclinedsurface (lower surface of the porous member 25) 2 as explained in thefifth embodiment. The fin member 150 is substantially triangular asviewed in a plan view. The fin members 150 are arranged in the bufferspace formed by the lower surface 2 of the porous member 25 at theinside of the wall portion 76. In this embodiment, each of the finmembers 150 has a thickness of about 0.1 mm. A large number of the finmembers 150 are arranged at intervals of 2 degrees in thecircumferential direction.

As shown in FIG. 13, recesses 14A are formed on the both sidesrespectively in the Y axis direction with respect to the projection areaAR1 of the projection optical system PL on the inner side surface 172Tof the inclined plate portion 172C of the second member 172. Therecesses 14A are formed in the direction of inclination of the inclinedplate portion 172C to form predetermined gaps G3 (see FIG. 15) withrespect to the side surface of the optical element LS1. The supply flowpassages 14 for supplying the liquid LQ to the image plane side of theprojection optical system PL are defined by the gaps G3 formed betweenthe recesses 14A and the optical element LS1. The upper end of thesupply flow passage 14 is connected to the liquid supply section 11 viaan unillustrated supply tube (supply flow passage), and the lower end isconnected to the gap (space) G2 between the bottom plate portion 172Dand the lower surface T1 of the projection optical system PL. The liquidsupply ports 12 for supplying the liquid LQ to the gap G2 are formed atthe lower ends. The liquid LQ, which is fed from the liquid supplysection 11, is supplied by the liquid immersion mechanism 1 via theliquid supply ports 12 provided at the lower ends of the flow passages14 to the space G2 between the projection optical system PL and thebottom plate portion 172D. In this embodiment, the supply flow passage14 is formed to have an inclination of about 45 degrees with respect tothe XY plane (surface of the substrate P).

Concave/convex portions may be provided, for example, on the uppersurface of the bottom plate portion 172D to control the flow velocity ofthe liquid and the flow direction of the liquid on the upper surface ofthe bottom plate portion 172D. For example, in order to determine theflow direction of the liquid LQ supplied to the upper surface 172A ofthe bottom plate portion 172D from the liquid supply port 12, afin-shaped member may be arranged for the liquid supply port 12, or afin-shaped projection may be provided on the upper surface 172A of thebottom plate portion 172D. In this case, it is preferable that the flowdirection of the liquid LQ and the flow rate of the liquid LQ areoptimized on the basis of a result of an experiment or simulation sothat the optical path space on the side of the image plane of theprojection optical system PL can be continuously filled with the liquidLQ without allowing any gas portion to remain. It is preferable that theflow direction of the liquid LQ and the flow rate of the liquid LQ areoptimized on the basis of a result of an experiment or simulation sothat the liquid LQ does not remain, for example, on the end surface T1of the optical element LS1 when substantially all of the liquid LQ isrecovered from the space on the side of the image plane of theprojection optical system PL to form the non-liquid immersion state.Alternatively, it is preferable that the flow direction of the liquid LQand the flow rate of the liquid LQ are optimized on the basis of aresult of an experiment or simulation so that the liquid, which containsany substance eluted from the substrate P (for example, anyphotosensitive resin), does not stay.

Further, slit-shaped through-holes 130, which penetrate in the directionof inclination through the inclined plate portion 172C of the secondmember 172, are formed on the both sides respectively of the secondmember 172 in the X axis direction with respect to the projection areaAR1. Openings, which are formed at the lower ends 130A of thethrough-holes 130, are connected to the gap (space) G2 between thebottom plate portion 172D and the lower surface T1 of the projectionoptical system PL. The upper ends 130B are open to the atmospheric air.The liquid can be fed along the upper surface 172A of the bottom plateportion 172D, i.e., in the directions parallel to the substrate from theopenings disposed at the lower ends 130A.

The groove 73, which is formed between the first member 171 and thesecond member 172, is arranged between the inclined surface 2 of theliquid recovery port 22 and the projection area AR1 onto which theexposure light beam EL is radiated. The groove 73 is formed to surroundthe opening 74 (projection area AR1). Further, the groove 73 is formedto surround the lower surface 172R for constituting a portion of theland surface 75 as well. In other words, the groove 73 is arrangedoutside the lower surface 172R for constituting the portion of the landsurface 75. The groove 73 has the opening 73A which is arranged oppositeto the upper surface of the substrate stage PST (substrate P supportedby the substrate stage PST). That is, the groove 73 is open so that thegroove 73 is directed downwardly. The opening 73A is provided in thevicinity of the image plane of the projection optical system PL. Thegroove 73 is communicated therein with the gas around the image plane ofthe projection optical system PL via the opening 73A.

The groove 73 has another opening 73B to be open to the atmospheric air,other than the opening 73A which is opposite to the substrate P(substrate stage PST). In this embodiment, the groove 73 has the opening73B which is disposed at the upper end and which is provided to be opento the atmospheric air. The opening 73B is formed to be annular asviewed in a plan view along the upper end of the groove 73. However, theopening 73B may be formed at only a portion of the upper end of thegroove 73. The position of the communication passage for making thecommunication between the inside and the outside of the groove 73 is notlimited to the upper end of the groove 73. The flow passage may beprovided at any position. For example, a flow passage, which makes thecommunication between the outside of the groove 73 and an intermediateposition (predetermined position) in the Z axis direction in the groove73, may be formed at a portion of the first member 171, and the groove73 may be open to the atmospheric air via the flow passage.

As described above, the groove 73B is formed, which has the opening 73Aopposite to the substrate P (substrate stage PST) and the opening 73B tobe open to the atmospheric air. Therefore, a part of the liquid LQ,which is disposed between the nozzle member 70′ and the substrate P(substrate stage PST), can enter into and exist out of the interior ofthe groove 73. Therefore, even when the size (diameter) of the nozzlemember 70′ is small, it is possible to suppress the outflow of theliquid LQ to the outside of the liquid recovery port 22.

As shown in FIG. 15, communication passages 131, which make thecommunication between the inside and the outside of the grooves 73, areformed at portions of the first member 171. A suction unit 132, whichincludes a vacuum system, is connected to the communication passage 131.The communication passages 131 and the suction unit 132 are used torecover the liquid LQ via the grooves 73 when the liquid LQ between thenozzle member 70′ and the substrate P (substrate stage PST), i.e., theliquid LQ for forming the liquid immersion area AR2 is completelyrecovered.

Next, an explanation will be made about the operation of the liquidimmersion mechanism 1 provided with the nozzle member 70′ constructed asdescribed above. In order to supply the liquid LQ onto the substrate P,the control unit CONT feeds the liquid LQ from the liquid supply section11 by driving the liquid supply section 11. The liquid LQ, which is fedfrom the liquid supply section 11, flows through the supply tube, andthen the liquid LQ flows into the upper ends of the supply flow passages14 of the nozzle member 70′. The liquid LQ, which is allowed flow intothe upper ends of the supply flow passages 14, is allowed flowdownwardly in the direction of inclination of the inclined plate portion172C. Then, the liquid LQ is supplied from the liquid supply ports 12 tothe space G2 between the bottom plate portion 172D and the end surfaceT1 of the projection optical system PL. In this case, any gas portion,which has been present in the space G2 before supplying the liquid LQ tothe space G2, is discharged to the outside via the through-holes 130and/or the opening 74. Therefore, it is possible to avoid the occurrenceof the inconvenience which would be otherwise caused such that the gasstays or remains in the space G2 upon the start of the supply of theliquid LQ to the space G2. It is possible to avoid the inconveniencewhich would be otherwise caused such that the gas portion (bubble) isgenerated in the liquid LQ.

The space G2 is filled with the liquid LQ supplied to the space G2.After that, the liquid LQ is allowed to flow into the space between theland surface 75 and the substrate P (substrate stage PST) via theopening 74. In this case, the liquid recovery mechanism 20 recovers theliquid LQ on the substrate P in a predetermined amount per unit time.Therefore, the liquid immersion area AR2, which has a desired size, isformed on the substrate P by the liquid LQ allowed to flow into thespace between the land surface 75 and the substrate P (substrate stagePST) via the opening 74.

In this embodiment, the opening 74, through which the exposure lightbeam EL is allowed to pass, has a small size, and the size of the landsurface 75 is relatively large. Therefore, the liquid LQ can be retainedsatisfactorily between the substrate P (substrate stage PST) and thenozzle member 70′.

The communication passage 131, which is connected to the groove 73, isclosed and the driving of the suction unit 132 is stopped during theperiod in which the liquid immersion area AR2 is formed, for example,during the period in which the substrate P is subjected to the liquidimmersion exposure. Therefore, even when the substrate P (substratestage PST) is moved with respect to the liquid immersion area AR2 formedto cover the projection area AR1, a part of the liquid LQ of the liquidimmersion area AR2 can enter into and exist out of the groove 73 whichis open to the atmospheric air. It is possible to avoid the occurrenceof the inconvenience which would be otherwise caused, for example, suchthat the liquid immersion area AR2 is expanded, and the liquid LQ of theliquid immersion area AR2 outflows. That is, for example, as shown inFIG. 16, when the substrate P is moved in the +X direction, the liquidLQ of the liquid immersion area AR2 also attempts to move in the +Xdirection in accordance with the movement of the substrate P. In thiscase, the following possibility may arise due to the movement of theliquid LQ in the +X direction. That is, the liquid immersion area AR2may be expanded in the +X direction, and the liquid LQ of the liquidimmersion area AR2 may outflow to the outside of the liquid recoveryport 22. However, a part of the liquid LQ moved in the +X directionenters the groove 73 disposed on the +X side, and the part of the liquidLQ is spread in the groove 73 (see the arrow F3 shown in FIG. 16).Therefore, it is possible to suppress, for example, the expansion of theliquid immersion area AR2 and the outflow of the liquid LQ.

When all of the liquid LQ between the nozzle member 70′ and thesubstrate P (substrate stage PST) is recovered, for example, when theliquid immersion exposure is completed for the substrate P, then thecontrol unit CONT performs the following operation. That is, the controlunit CONT stops the liquid supply operation by the liquid supplymechanism 10 so as to perform the liquid recovery operation via theliquid recovery port 22 by the liquid recovery mechanism 20. Further,the control unit CONT opens the communication passage 131, which isconnected to the groove 73, and drives the suction unit 132 so that theinternal space of the groove 73 is allowed to have the negative pressureto concurrently perform the liquid recovery operation via the opening73A of the groove 73 as well. Accordingly, the liquid LQ, which isbetween the nozzle member 70′ and the substrate P (substrate stage PST),can be reliably recovered in a short period of time by using the opening73A disposed most closely to the substrate P (substrate stage PST) aswell, as described above. In this case, the opening 73B, which isprovided to be open to the atmospheric air, is smaller in size than theopening 73A which functions as the recovery port for the liquid LQ.Therefore, the liquid LQ can be recovered while allowing the interior ofthe groove 73 to have the sufficient negative pressure.

When the liquid LQ is recovered via the groove 73, there is such apossibility that the gas present in the groove 73 may flow into thecommunication passage 131 together with the liquid LQ, and any vibrationmay be generated on the nozzle member 70′. However, no problem arises,because the recovery of the liquid LQ, which is performed via the groove73, is executed when the operation such as the exposure operation forthe substrate P, which requires the accuracy, is not performed.

In this embodiment, the recesses 14A (two in total) for forming thesupply flow passages 14 are provided one by one on the both sides,respectively, in the Y axis direction with respect to the projectionarea AR1. However, the recesses 14A may be provided at a plurality ofarbitrary positions to surround the projection area AR1, of theprojection optical system PL, onto which the exposure light beam EL isradiated. The bank 15 (buffer flow passage portion 14H) as explained inthe first embodiment may be also provided at a position in the vicinityof the upper end of the recess 14A.

Seventh Embodiment

Next, a seventh embodiment of the present invention will be explainedwith reference to FIGS. 17 and 18. Mechanisms and members, which are thesame as or similar to those of the respective embodiments describedabove, are designated by common reference numerals, and any detailedexplanation of which will be omitted. FIG. 17 shows a nozzle member 70′as viewed from the lower side, and FIG. 18 shows a side sectional view.With reference to FIGS. 17 and 18, the seventh embodiment is differentfrom the sixth embodiment described above in that a bottom plate portion172D of the second member 72 has a small size, and the bottom plateportion 172D is scarcely arranged between the substrate P (substratestage PST) and the lower surface T1 of the projection optical system PL.That is, an opening 74, which is formed through the bottom plate portion172D, is formed to have a substantially circular shape which hasapproximately the same size as that of the lower surface T1 of theprojection optical system PL (optical element LS1) and which issufficiently larger than the projection area AR1. Almost all of thelower surface T1 of the optical element LS1 is exposed to be opposite tothe substrate P (substrate stage PST). The liquid LQ, which is fed fromthe liquid supply section 11, is supplied to the space between thesubstrate P (substrate stage PST) and the lower surface T1 of theprojection optical system PL via the supply flow passages 14 formedbetween the recesses 14A and the side surface of the optical elementLS1. In this embodiment, although the areal size of the land surface 75is small, the space is scarcely formed between the bottom plate portion172 and the optical element LS1 of the projection optical system PL, andthe portion, at which the gas tends to stay or remain, is decreased ascompared with the sixth embodiment. Therefore, it is possible to morereliably avoid the inconvenience which would be otherwise caused suchthat the gas portion (bubble) is generated in the liquid LQ for formingthe liquid immersion area AR2 when the supply of the liquid LQ isstarted.

In the sixth embodiment and the seventh embodiment described above, thenozzle member 70′ is constructed by combining the first member 171 andthe second member 172 in order to simplify the explanation. However, inpractice, the nozzle member 70′ is constructed by further combiningseveral other members. It is a matter of course that the nozzle member70′ may be constructed of one member.

In the sixth embodiment and the seventh embodiment described above, thegas present in the space G2 is discharged by using the through-holes 130upon the start of the supply of the liquid LQ. However, thethrough-holes 130 may be connected to the suction unit (vacuum system),and the gas present in the space G2 may be forcibly discharged upon thestart of the supply of the liquid LQ.

In the sixth embodiment and the seventh embodiment described above, theopening 74 of the bottom plate portion 172D is not limited to the shapesshown in FIGS. 14 and 17. The shape of the opening 74 of the bottomplate portion 172D can be determined so that the gas portion does notremain, and the optical path space on the side of the image plane of theprojection optical system PL can be continuously filled with the liquidLQ even when the substrate P (substrate stage PST) is moved.

In the sixth embodiment and the seventh embodiment described above, whenall of the liquid LQ, which is between the nozzle member 70′ and thesubstrate P (substrate stage PST) (in the optical path space on the sideof the image plane of the projection optical system PL), is recovered,any gas may be blown from the liquid supply port 12 in addition to theliquid recovery operation using the liquid recovery port 22 and theopening 73A. The gas, which is blown from the liquid supply port 12, isblown to the lower surface T1 of the optical element LS1 disposed at theend portion of the projection optical system PL. Therefore, it ispossible to remove the liquid LQ adhering (remaining) on the lowersurface T1 of the optical element LS1. The gas, which is blown from theliquid supply port 12, flows along the lower surface T. The liquid(liquid droplet) LQ, which is adhered to an area of the lower surface T1of the optical element LS1 through which the exposure light beam ELpasses, i.e., an area of the lower surface T1 of the optical element LS1corresponding to the projection area AR1, can be moved (retracted) tothe outside of the area. Accordingly, the liquid LQ, which has beenadhered to the area of the lower surface T1 of the optical element LS1through which the exposure light beam EL passes, is removed. The liquidLQ may be removed by evaporating or vaporizing (drying) the liquid LQadhered to the lower surface T1 of the optical element LS1 by the gasallowed to blow thereto. A clean gas, which is obtained by the aid of afilter unit (not shown) including a chemical filter and/or aparticle-removing filter, is allowed to blow from the liquid supply port12. The gas to be used is the gas, for example, air (dry air) which isapproximately the same as the gas in the chamber in which the exposureapparatus EX is accommodated. The nitrogen gas (dry nitrogen) may beused as the gas allowed to be blown. When all of the liquid LQ isrecovered, then a vacuum system or the like may be connected to thethrough-holes 130 which are provided to discharge the gas existing inthe space G2 to the outside, and the liquid LQ may be sucked andrecovered from the openings which are formed at the lower ends of thethrough-holes 130. Alternatively, a gas supply system may be connectedto the through-holes 130 which are provided to discharge the gasexisting in the space G2 to the outside, and the gas may be blownthrough the through-holes 130.

In the sixth and seventh embodiments, the liquid supply ports 12 may bearranged on the both sides, respectively, in the X axis direction withrespect to the projection area AR1 respectively, and the liquid LQ maybe supplied from the both sides in the scanning direction respectively.In this case, the lower ends 130A of the through-holes 130 are providedat positions different from those of the liquid supply ports 12, forexample, on the both sides in the Y axis direction with respect to theprojection area AR1.

In the sixth and seventh embodiments, the supply flow passages 14 areformed by the gaps G3 between the recesses 14A of the inclined plateportion 172C and the side surface of the optical element LS1, and thelower ends of the supply flow passages 14 function as the liquid supplyports 12. However, the upper ends 130B of the through-holes 130 may beconnected to the liquid supply section 11, the through-holes 130 may beallowed to function as supply flow passages, and the lower ends 130A ofthe through-holes 130 may be allowed to function as liquid supply ports.When the upper ends 130B of the through-holes 130 are connected to theliquid supply section 11 to supply the liquid LQ via the through-holes130, then the liquid supply section 11 is not connected to the gaps G3between the recesses 14A of the inclined plate portion 172C and the sidesurface of the optical element LS1 (gaps G3 do not function as thesupply flow passages), and the upper ends of the gaps G3 are open to theatmospheric air. The gas, which exists in the space G2, is discharged tothe outside via the gaps G3 before the liquid LQ is supplied to thespace G2 from the through-holes 130. Even when the liquid LQ is suppliedvia the through-holes 130, it is possible to avoid the occurrence of theinconvenience which would be otherwise caused such that the gas stays orremains in the space G2 upon the start of the supply of the liquid LQ tothe space G2. It is possible to avoid the inconvenience which would beotherwise caused such that the gas portion (bubble) is generated in theliquid LQ. Also in this case, the upper ends of the gaps G3 may beconnected to the suction unit (vacuum system), and the gas present inthe space G2 may be forcibly discharged upon the start of the supply ofthe liquid LQ.

When the liquid LQ is supplied via the through-holes 130, then the lowerends 130A of the through-holes 130, which function as the liquid supplyports, may be arranged on the both sides, respectively, in the Y axisdirection with respect to the projection area AR1, and the liquid LQ maybe supplied from the both sides respectively in the non-scanningdirection.

Eighth Embodiment

Next, an eighth embodiment of the present invention will be explainedwith reference to FIGS. 19, 20, 21, and 22. FIG. 19 shows, with partialcutout, a schematic perspective view illustrating those disposed in thevicinity of a nozzle member 70″. FIG. 20 shows a perspective viewillustrating the nozzle member 70″ as viewed from the lower side. FIG.21 shows a side sectional view taken in parallel to the YZ plane. FIG.22 shows a side sectional view taken in parallel to the XZ plane. In thefollowing description, constitutive parts, which are the same as orequivalent to those of the embodiments described above, are designatedby the same reference numerals, and any explanation of which will besimplified or omitted.

The nozzle member 70″ is constructed by combining a first member 171, asecond member 172, and a third member 173. The nozzle member 70″ isformed to be substantially circular as viewed in a plan view as a whole.The first member 171 has a side plate portion 171A and a thick-walledinclined plate portion 171C. The second member 172 has an inclined plateportion 172C and a bottom plate portion 172D connected to the lower endof the inclined plate portion 172C. The third member 173 is connected tothe upper ends of the first member 171 and the second member 172. A hole173H, in which the optical element LS1 is to be arranged, is formed at acentral portion of the third member 173. The optical element LS1 isarranged inside the hole 70H which is defined by the hole 173H of thethird member 173 and the inclined plate portion 172C of the secondmember 172. The side surface of the optical element LS1 arranged insidethe hole 70H is opposite to the inner side surface 172T of the inclinedplate portion 172C of the second member 172. A slit-shaped groove 73,which is annular as viewed in a plan view, is provided between the innerside surface 171T of the inclined plate portion 171C of the first member171 and the outer side surface 172S of the inclined plate portion 172Cof the second member 172. The groove 73 is formed to have an inclinationof about 45 degrees with respect to the XY plane (surface of thesubstrate P).

A land surface 75 of the nozzle member 70″, which is opposite to thesurface of the substrate P supported by the substrate stage PST (uppersurface of the substrate stage PST) and which is disposed most closelyto the surface of the substrate P (upper surface of the substrate stagePST), is formed by the lower surface 171R of the inclined plate portion171C of the first member 171 and the lower surface 172R of the bottomplate portion 172D of the second member 172. The land surface 75 isformed to surround the projection area AR1.

A portion of the bottom plate portion 172D for forming the land surface75 is arranged between the substrate P (substrate stage PST) and thelower surface T1 on the side of the image plane of the optical elementLS1 of the projection optical system PL in relation to the Z axisdirection. The bottom plate portion 172D is provided to make no contactwith the lower surface T1 of the optical element LS1 and the substrate P(substrate stage PST). The upper surface of the bottom plate portion172D is arranged so that the upper surface of the bottom plate portion172D is opposite to the lower surface T1 of the optical element LS1, andthe upper surface of the bottom plate portion 172D is substantially inparallel to the lower surface of the optical element. A predeterminedgap (space) G2 is formed between the end surface T1 of the projectionoptical system PL and the upper surface of the bottom plate portion172D.

A space 24, which functions as the recovery flow passage, is formed forthe first member 171. The liquid recovery port 22 is formed at theopening of the space 24. A liquid recovery port 22 is formed to beannular as viewed in a plan view to surround the opening 74 (projectionarea AR1), the groove 73, and the land surface 75. The other end of therecovery tube 23 is connected to a portion of the recovery flow passage(space) 24. A porous member 25, which has an inclined surface 2 oppositeto the substrate P supported by the substrate stage PST, is arranged inthe liquid recovery port 22. The porous member 25 is attached to theliquid recovery port 22 so that the inner edge portion of the inclinedsurface 2 has approximately the same height as that of the lower surface171R (land surface 75) of the first member 171, and the inner edgeportion of the inclined surface 2 is continued to the lower surface 171R(land surface 75). A plurality of fin members 150 are provided radiallyon the inclined surface 2.

Slit-shaped through-holes 140, which penetrate in the inclinationdirection through the inclined plate portion 172C of the second member172, are formed on the both sides, respectively, in the Y axis directionof the second member 172 with respect to the projection area AR1. Theupper end 140B of the through-hole 140 is connected to the liquid supplysection 11 via an unillustrated supply tube (supply flow passage), andthe lower end 140A is connected to the gap (space) G2 between the bottomplate portion 172D and the lower surface T1 of the projection opticalsystem PL. That is, the through-holes 140 function as the supply flowpassages. The openings, which are formed at the lower ends 140A of thethrough-holes 140, function as the liquid supply ports for supplying theliquid LQ to the gap G2. The liquid supply ports 140A are provided onthe both sides in the Y axis direction respectively while interposingthe projection area AR1 onto which the exposure light beam EL isradiated. The liquid supply ports 140A are provided at the predeterminedpositions (first positions), respectively, disposed on the both sideswith the optical path space for the exposure light beam EL interveningtherebetween, and at the outside of the optical path space for theexposure light beam EL.

The liquid immersion mechanism 1 supplies the liquid LQ, fed from theliquid supply section 11, via the supply flow passages (through-holes)140 from the liquid supply ports (lower ends) 140A to the internal spaceincluding the gap (space) G2 between the projection optical system PLand the bottom plate portion 172D. The supply flow passage 140 is formedto have an inclination of about 45 degrees with respect to the XY plane(surface of the substrate P). In order to determine the flow directionof the liquid LQ supplied to the upper surface of the bottom plateportion 172D from the liquid supply ports 140A, a fin-shaped member maybe arranged for the liquid supply port 140A, or a fin-shaped projectionmay be provided on the upper surface of the bottom plate portion 172D.

Slit-shaped through-holes 130, which penetrate in the inclinationdirection through the inclined plate portion 172C of the second member172, are formed on the both sides, respectively, in the X axis directionof the second member 172 with respect to the projection area AR1. A gapis formed between the third member 173 and a predetermined area of theupper surface of the second member 172 in which the upper end 130B ofthe through-hole 130 is formed. The upper end 130B of the through-hole130 is open to the atmospheric air. The lower end 130A of thethrough-hole 130 is connected to the gap (space) G2 between the bottomplate portion 172D and the lower surface T1 of the projection opticalsystem PL. Therefore, the gas present in the gap G2 can be discharged(exhausted) to the external space via the upper ends 130B of thethrough-holes 130. That is, the openings, which are formed at the lowerends 130A of the through-holes 130, function as the gas discharge portsfor discharging the gas present in the gap G2. The through-holes 130function as the discharge flow passages. The gas discharge ports (lowerends) 130A are connected to the gas present in the gap (space) G2, i.e.,the gas around the image plane of the projection optical system PL. Thegas discharge ports 130A are provided on the both sides, respectively,in the X axis direction while interposing the projection area AR1 ontowhich the exposure light beam EL is radiated. The gas discharge ports130A are provided at the predetermined positions (second positions),respectively, which are disposed on the both sides with the optical pathspace for the exposure light beam EL intervening therebetween, at theoutside of the optical path space for the exposure light beam EL.

As described above, the liquid supply ports 140A are provided at thepredetermined positions (first positions) disposed outside the opticalpath space for the exposure light beam EL. The bottom plate portion 172Dfunctions also as a guide member for guiding the flows of the liquid LQsupplied from the liquid supply ports 140A. The bottom plate portion(guide member) 172D is arranged to prevent the gas from staying orremaining in the liquid LQ in the optical path space for the exposurelight beam EL. That is, the bottom plate portion 172D is arranged sothat the liquid LQ, which is supplied from the liquid supply ports 140Aprovided at the first positions disposed outside the optical path spacefor the exposure light beam EL, is allowed to flow, via the optical pathspace for the exposure light beam EL, toward the second positions whichare different from the first positions disposed outside the optical pathspace. The bottom plate portion 172D has the land surface (flat portion)75 which is arranged opposite to the substrate P. The bottom plateportion 172D also functions to stably fill the optical path for theexposure light beam EL with the liquid LQ in the same manner as in theembodiment described above.

FIG. 23 shows a plan view illustrating the bottom plate portion (guidemember) 172D. In this embodiment, the gas discharge ports 130A areprovided at the second positions disposed outside the optical path spacefor the exposure light beam EL. The bottom plate portion 172D isarranged so that the liquid LQ, which is supplied from the liquid supplyports 140A, is allowed to flow toward the second positions at which thegas discharge ports 130A are provided. The guide member 172D makes theliquid LQ to flow so that any vortex flow is not formed in the opticalpath space for the exposure light beam EL. That is, the bottom plateportion 172D has an opening 74′ which is formed so that the liquid LQ,which is supplied from the first positions at which the liquid supplyports 140A are arranged, is allowed to flow toward the second positionsat which the gas discharge ports 130A are provided. The formation of anyvortex flow is avoided in the optical path space for the exposure lightbeam EL.

The bottom plate portion 172D includes first guide portions 181 whichform the flows directed from the first positions at which the liquidsupply ports 140A are provided toward the optical path space for theexposure light beam EL (projection area AR1), and second guide portions182 which form the flows directed from the optical path space for theexposure light beam EL toward the second positions at which the gasdischarge ports 130A are provided. That is, flow passages 181F, whichmake the liquid LQ to flow from the liquid supply ports 140A toward theoptical path space for the exposure light beam EL, are formed by thefirst guide portions 181. Further, flow passages 182F, which make theliquid LQ to flow from the optical path space for the exposure lightbeam EL toward the second positions (gas discharge ports 130A), areformed by the second guide portions 182.

The flow passages 181F formed by the first guide portions 181 intersectthe flow passages 182F formed by the second guide portions 182. The flowpassages 181F formed by the first guide portions 181 allow the liquid LQto flow substantially in the Y axis direction. The flow passages 182Fformed by the second guide portions 182 make the liquid LQ to flowsubstantially in the X axis direction. The opening 74′, which has asubstantially cross-shaped form as viewed in a plan view, is formed bythe first guide portions 181 and the second guide portions 182. Theopening 74′ is arranged on the side of the image plane of the projectionoptical system PL. The opening 74′ is provided so that the exposurelight beam EL passes through a substantially central portion of theopening 74′ formed to have the substantially cross-shaped form. That is,the optical path space for the exposure light beam EL is set at theportion of intersection between the flow passages 181F formed by thefirst guide portions 181 and the flow passages 182F formed by the secondguide portions 182.

In this embodiment, the flow passages 181F formed by the first guideportions 181 are substantially perpendicular to the flow passages 182Fformed by the second guide portions 182. A width D1 of the flow passages181F formed by the first guide portions 181 is approximately the same asa width D2 of the flow passages 182F formed by the second guide portions182. In this embodiment, connecting portions 190 between the first guideportions 181 and the second guide portions 182 are formed to be curved(circular arc-shaped).

The liquid supply ports 140A supply the liquid LQ to the internal spaceincluding the gap (space) G2 between the bottom plate portion 172D andthe lower surface T1 of the projection optical system PL. The liquid LQ,which is supplied to the gap G2 from the liquid supply ports 140A, isallowed to flow toward the optical path space for the exposure lightbeam EL while being guided by the first guide portions 181. The liquidLQ passes through the optical path space for the exposure light beam EL,and then the liquid LQ is allowed to flow toward the outside of theoptical path space for the exposure light beam EL while being guided bythe second guide portions 182. That is, the flow passages for the liquidLQ are bent at the position of intersection between the first guideportions 181 and the second guide portions 182 or in the vicinitythereof. In another viewpoint, the flow passages for the liquid LQ arebent in the optical path space or in the vicinity thereof. The liquidimmersion mechanism 1 suppresses the formation of the vortex flow in theoptical path space for the exposure light beam EL by allowing the liquidLQ to flow while being guided by the first and second guide portions181, 182 of the bottom plate portion 172D. Accordingly, even when thegas (bubble) is present in the optical path space for the exposure lightbeam EL, then the gas (bubble) is discharged to the second positionsdisposed outside the optical path space for the exposure light beam EL,and the gas (babble) is prevent from remaining in the optical path spacefor the exposure light beam EL.

As shown in FIGS. 19 and 21, for example, the groove 73, which isdisposed between the first member 171 and the second member 172, isformed to surround the opening 74′ including the optical path space forthe exposure light beam EL. Further, the groove 73 is formed to surroundthe lower surface 172R for constructing a part of the land surface 75 aswell. An opening 73A, which is arranged opposite to the substrate P(upper surface of the substrate stage PST), is formed at the lower endof the groove 73. The opening 73A is formed to be substantially annularas viewed in a plan view. On the other hand, an opening 73B, which issubstantially annular as viewed in a plan view, is also formed at theupper end of the groove 73. A cutout 171K is formed at a portion of theupper end of the inclined plate portion 171C of the first member 171,the portion being opposite to the second member 172. A wide widthportion is defined at the upper end of the groove 73 by the cutout 171K.A space 73W is defined between the wide width portion and the thirdmember 173. The opening 73B, which is disposed at the upper end of thegroove 73, is arranged inside the space 73W. The space 73W is connectedvia the groove 73 to the opening 73A which is provided at the lower endof the groove 73 (in the vicinity of the image plane of the projectionoptical system PL). That is, the space 73W is communicated with the gasaround the image plane of the projection optical system PL via thegroove 73 (opening 73A).

As shown in FIG. 21, a communication passage 131′, which is connected tothe space 73W, is formed at a portion of the third member 173. Thecommunication passage 131′ is connected via a piping 133 to a suctionunit 132 including a vacuum system. The communication passage 131′ andthe suction unit 132 are used to recover the liquid LQ via the groove 73when the liquid LQ, which is between the nozzle member 70″ and thesubstrate P (substrate stage PST), is completely recovered.

A hole 134, which makes the communication between the inside and theoutside of the space 73W, is formed at a position of the third member173, the position being distinct or different from the communicationpassage 131′. The diameter (size) of the hole 134 is smaller than thediameter (size) of the communication passage 131′ and sufficientlysmaller than the opening 73A. In this embodiment, the diameter of thehole 134 is about 1 mm. The space 73W is open to the atmospheric air bythe hole 134. Accordingly, the gas (space G2), which is around the imageplane of the projection optical system PL, is also open to theatmospheric air via the opening 73A, the groove 73, and the space 73W.Accordingly, a part of the liquid LQ between the nozzle member 70″ andthe substrate P (substrate stage PST) can enter and exist the inside ofthe groove 73. Therefore, even when the size (diameter) of the nozzlemember 70″ is small, it is possible to suppress the outflow of theliquid LQ to the outside of the liquid recovery port 22.

Next, an explanation will be made about the operation of the liquidimmersion mechanism 1 having the nozzle member 70″ constructed asdescribed above. In order to supply the liquid LQ onto the substrate P,the control unit CONT drives the liquid supply section 11 to feed theliquid LQ from the liquid supply section 11. The liquid LQ, which is fedfrom the liquid supply section 11, is allowed to flow through the supplytube, and then the liquid LQ flows into the upper ends 140B of thesupply flow passages 140 of the nozzle member 70″. The liquid LQ, whichflows into the upper ends 140B of the supply flow passages 140, isallowed to flow through the supply flow passages 140. Then, the liquidLQ is supplied from the liquid supply ports 140A to the space G2 betweenthe bottom plate portion 172D and the end surface T1 of the projectionoptical system PL. The gas portion, which has been present in the spaceG2 before the liquid LQ is supplied to the space G2, is discharged tothe outside via the through-holes 130 and the opening 74′. Therefore, itis possible to avoid the occurrence of the inconvenience which would beotherwise caused such that the gas stays or remains in the space G2 uponthe start of the supply of the liquid LQ to the space G2. It is possibleto avoid the occurrence of the inconvenience which would be otherwisecaused such that the gas portion (bubble) is generated in the liquid LQ.The liquid LQ, which is fed from the liquid supply section 11, flowsthrough the inside of the grooves (supply flow passages) 140. Therefore,the liquid LQ is supplied to the space G2 without exerting any force,for example, on the side surface of the optical element LS1. Further,the liquid LQ makes no contact with the side surface of the opticalelement LS1. Therefore, for example, even when the side surface of theoptical element LS1 is coated with a predetermined functional material,any influence, which would be otherwise exerted on the functionalmaterial, is suppressed.

The space G2 is filled with liquid LQ which is supplied to the space G2.After that, the liquid LQ is allowed to flow via the opening 74′ intothe space between the land surface 75 and the substrate P (substratestage PST). In this case, the liquid recovery mechanism 20 recovers theliquid LQ on the substrate P in a predetermined amount per unit time.Therefore, the liquid immersion area AR2 having a desired size is formedon the substrate P by the liquid LQ allowed to flow via the opening 74′into the space between the land surface 75 and the substrate P(substrate stage PST).

The liquid LQ, which is supplied from the liquid supply ports 140A tothe space G2, is allowed to flow toward the optical path space for theexposure light beam EL (projection area AR1) while being guided by thefirst guide portions 181. After that, the liquid LQ is allowed to flowto the outside of the optical path space for the exposure light beam ELwhile being guided by the second guide portions 182. Therefore, even ifany gas portion (bubble) is generated in the liquid LQ, the bubble canbe discharge to the outside of the optical path space for the exposurelight beam EL by the flow of the liquid LQ. The bottom plate portion172D allows the liquid LQ to flow so that any vortex flow is not formedin the optical path space for the exposure light beam EL. Therefore, itis possible to prevent the bubble from staying or remaining in theoptical path space for the exposure light beam EL. The bottom plateportion 172D allows the liquid LQ to flow toward the gas discharge ports130A. Therefore, any gas portion (bubble), which is present in theliquid LQ, is smoothly discharged to the outside via the gas dischargeports 130A. Even if any gas portion (bubble) is present in the liquid LQin the space between the land surface 75 and the substrate P (substratestage PST), the liquid LQ, which is in the space between the landsurface 75 and the substrate P (substrate stage PST), is recoveredtogether with the gas portion (bubble) via the recovery port 22.

The communication passage 131′, which is connected to the groove 73, isclosed, and the driving of the suction unit 132 is stopped during theperiod in which the liquid immersion area AR2 is formed, for example,during the period in which the substrate P is subjected to the liquidimmersion exposure. Therefore, even when the substrate P (substratestage PST) is moved with respect to the liquid immersion area AR2 formedto cover the projection area AR1, a part of the liquid LQ of the liquidimmersion area AR2 enters and exits the groove 73 which is open to theatmospheric air via the hole 134 (see the arrow F3 shown in FIG. 22).Therefore, it is possible to avoid the occurrence of the inconveniencewhich would be otherwise caused, for example, such that the liquidimmersion area AR2 is expanded and the liquid LQ of the liquid immersionarea AR2 outflows.

When all of the liquid LQ between the nozzle member 70″ and thesubstrate P (substrate stage PST) is recovered, for example, when theliquid immersion exposure is completed for the substrate P, then thecontrol unit CONT performs the following operation. That is, the controlunit CONT performs the liquid recovery operation via the liquid recoveryport 22 by the liquid recovery mechanism 20, and opens the communicationpassage 131′, which is connected to the groove 73, and the control unitCONT drives the suction unit 132 so that the internal space of thegroove 73 is allowed to have the negative pressure, while concurrentlyperforming the liquid recovery operation via the opening 73A of thegroove 73. The liquid LQ, which is between the nozzle member 70″ and thesubstrate P (substrate stage PST), can be reliably recovered in ashorter period of time by also using the opening 73A disposed mostclosely to the substrate P (substrate stage PST) as well, as describedabove. In this case, the hole 134, which is provided to be open to theatmospheric air, is smaller in size than the opening 73A which functionsas the recovery port for the liquid LQ. Therefore, the liquid LQ can berecovered while allowing the interior of the groove 73 to have thesufficient negative pressure. When all of the liquid LQ, which isbetween the nozzle member 70″ and the substrate P (substrate stage PST),is recovered, the gas may be blown from the liquid supply ports 140 inaddition to the liquid recovery operation using the liquid recovery port22 and the opening 73A.

The communication passage 131′, which is connected to the groove 73, maybe opened, and the suction unit 132 may be driven as well, to such anextent that the state (for example, the shape) of the liquid immersionarea AR2 can be maintained during the period in which the liquidimmersion area AR2 is formed, for example, during the period in whichthe substrate P is subjected to the liquid immersion exposure.Accordingly, the bubble present in the liquid LQ can be recovered viathe groove 73.

As shown in FIG. 24, the upper ends 130B of the grooves 130 may beconnected to the suction unit (suction system) 135, and the gasdischarge ports 130A may be connected to the suction unit 135 via thegrooves 130. For example, the suction unit 135 may be driven to providethe negative pressure at the inside of the grooves 130 upon the start ofthe supply of the liquid LQ for forming the liquid immersion area AR2,and the gas present in the space G2 may be forcibly discharged. In thisway, it is also possible to avoid the occurrence of the inconveniencewhich would be otherwise caused such that the gas stays or remains inthe space G2. It is possible to avoid the inconvenience which would beotherwise caused such that any gas portion (bubble) is generated orformed in the liquid LQ. The substrate P may be subjected to the liquidimmersion exposure while driving the suction unit 135. The driving ofthe suction unit 135 may be stopped during the liquid immersion exposurefor the substrate P.

The nozzle member 70″ is constructed of the three members, i.e., thefirst, second, and third members 171, 172, 173. However, the nozzlemember 70″ may be constructed of one member. Alternatively, the nozzlemember 70″ may be constructed of a plurality of members other than thethree members.

Ninth Embodiment

FIG. 25 shows a ninth embodiment. The feature of this embodiment is thatthe width D2 of the flow passages 182F formed by the second guideportions 182 is smaller than the width D1 of the flow passages 181Fformed by the first guide portions 181. Accordingly, it is possible toincrease the flow rate of the liquid LQ allowed to flow through the flowpassages 182F formed by the second guide portions 182 as compared withthe flow rate of the liquid LQ allowed to flow through the flow passages181F formed by the first guide portions 181. Therefore, the gas(bubble), which is present in the optical path space for the exposurelight beam EL, can be discharged quickly and smoothly to the outside ofthe optical path space for the exposure light beam EL by the flow of theliquid LQ allowed to have a high velocity.

Tenth Embodiment

FIG. 26 shows a tenth embodiment. The feature of this embodiment is thatthe width D2 of the flow passages 182F formed by the second guideportions 182 is formed and progressively narrowed from the optical pathspace for the exposure light beam EL (upstream side of the projectionarea AR1 or the second guide portion 182) toward the second positions atwhich the gas discharge ports 130A are provided (downstream side of thesecond guide portion 182). Even in the case of the arrangement asdescribed above, it is possible to increase the flow rate of the liquidLQ allowed to flow through the flow passages 182F formed by the secondguide portions 182 as compared with the flow rate of the liquid LQallowed to flow through the flow passages 181F formed by the first guideportions 181. The gas (bubble) can be discharged quickly and smoothly tothe outside of the optical path space for the exposure light beam EL.

Eleventh Embodiment

FIG. 27 shows an eleventh embodiment. The feature of this embodiment isthat connecting portions 190 between the first guide portions 181 andthe second guide portions 182 are formed to be linear, and corners areformed between the first guide portions 181 and the second guideportions 182. Even in the case of the arrangement as described above, itis possible to suppress the formation of the vortex flow, and it ispossible to prevent the gas (bubble) from staying or remaining in theliquid LQ in the optical path space for the exposure light beam EL. Thegas (bubble) can be discharged to the outside of the optical path spacefor the exposure light beam EL.

Twelfth Embodiment

FIG. 28 shows a twelfth embodiment. The feature of this embodiment isthat predetermined areas (flow passage widths thereof) of the flowpassages 181F formed by the first guide portions 181, which are disposedin the vicinity of the liquid supply ports 140A, are formed to beprogressively narrowed from the liquid supply ports 140A toward theoptical path space for the exposure light beam EL (projection area AR1)(progressively narrowed from the upstream to the downstream), andpredetermined areas (flow passage widths thereof) of the flow passages182F formed by the second guide portions 182, which are disposed in thevicinity of the gas discharge ports 130A, are formed to be progressivelyexpanded or widened from the optical path space for the exposure lightbeam EL (projection area AR1) toward the gas discharge ports 130A(progressively expanded or widened from the upstream to the downstream).In this embodiment, the first guide portions 181 intersect the secondguide portions 182 substantially perpendicularly. Even in the case ofthe arrangement as described above, it is possible to suppress theformation of the vortex flow, and it is possible to prevent the gas(bubble) from staying or remaining in the liquid LQ in the optical pathspace for the exposure light beam EL. The gas (bubble) can be dischargedto the outside of the optical path space for the exposure light beam EL.

Thirteenth Embodiment

FIG. 29 shows a thirteenth embodiment. The feature of this embodiment isthat only one liquid supply port 140A is provided. The flow passage 181Fformed by the first guide portion 181 is substantially perpendicular tothe flow passages 182F formed by the second guide portions 182. Theopening 74′ is formed to be substantially T-shaped as viewed in a planview. Even in the case of the arrangement as described above, it ispossible to suppress the formation of the vortex flow, and it ispossible to prevent the gas (bubble) from staying or remaining in theliquid LQ in the optical path space for the exposure light beam EL. Thegas (bubble) can be discharged to the outside of the optical path spacefor the exposure light beam EL.

Fourteenth Embodiment

FIG. 30 shows a fourteenth embodiment. The feature of this embodiment isthat the flow passages 181F formed by the first guide portions 181 arenot perpendicular to the flow passages 182F formed by the second guideportions 182, and they make the intersection at a predetermined angleother than 90 degrees. The liquid supply ports 140A (first positions)are provided at positions deviated in the θZ direction from thepositions aligned with the projection area AR1 in relation to the Y axisdirection, in the areas disposed outside the optical path space for theexposure light beam EL (projection area AR1). The gas discharge ports130A (second positions) are also provided at positions deviated in theθZ direction from the positions aligned with the projection area AR1 inrelation to the X axis direction. Even in the case of the arrangement asdescribed above, it is possible to suppress the formation of the vortexflow, and it is possible to prevent the gas (bubble) from staying in theliquid LQ in the optical path space for the exposure light beam EL. Thegas (bubble) can be discharged to the outside of the optical path spacefor the exposure light beam EL.

Fifteenth Embodiment

FIG. 31 shows a fifteenth embodiment. The feature of this embodiment isthat the liquid supply ports 140A and the gas discharge ports 130A areprovided at three predetermined positions, respectively, in the areasdisposed outside the optical path space for the exposure light beam EL.In this case, the liquid supply ports 140A and the gas discharge ports130A are alternately arranged at substantially equal intervals tosurround the optical axis AX of the projection optical system PL in thearea disposed outside the optical path space for the exposure light beamEL (projection area AR1). The plurality of flow passages 181F formed bythe first guide portions 181 intersect the plurality of flow passages182F formed by the second guide portions 182 at predetermined angles,respectively. Even in the case of the arrangement as described above, itis possible to suppress the formation of the vortex flow, and it ispossible to prevent the gas (bubble) from staying or remaining in theliquid LQ in the optical path space for the exposure light beam EL. Thegas (bubble) can be discharged to the outside of the optical path spacefor the exposure light beam EL.

Sixteenth Embodiment

FIG. 32 shows a sixteenth embodiment. The feature of this embodiment isthat the liquid supply ports 140A (first positions) are provided atpositions aligned with the projection area AR1 in relation to the Y axisdirection in the areas disposed outside the optical path space for theexposure light beam EL (projection area AR1), and the gas dischargeports 130A (second positions) are provided at positions deviated in theθZ direction from the positions aligned with the projection area AR1 inrelation to the X axis direction. In this embodiment, the gas dischargeports 130A are provided at the positions deviated by approximately 45degrees in the θZ direction from the positions aligned with theprojection area AR1 in relation to the X axis direction in the areasdisposed outside the optical path space for the exposure light beam EL(projection area AR1). The bottom plate portion (guide member) 172D hasthe first guide portions 181 which form the flows directed from theliquid supply ports 140A toward the optical path space for the exposurelight beam EL, and the second guide portions 182 which form the flowsdirected from the optical path space for the exposure light beam ELtoward the gas discharge ports 130A. The flow passages 181F, which areformed by the first guide portions 181, allow the liquid LQ to flowsubstantially in the Y axis direction. On the other hand, the flowpassages 182F, which are formed by the second guide portions 182, havefirst areas 182Fa which are perpendicular to the flow passages 181F andwhich allow the liquid LQ to flow substantially in the X axis directionand second areas 182Fb which allow the liquid LQ, allowed to flowthrough the first areas 182Fa, to flow toward the gas discharge ports130A. The opening 74′, which is substantially cross-shaped as viewed ina plan view, is formed by the flow passages 181F and the first areas182Fa of the flow passages 182F. According to the arrangement asdescribed above, even when the positions for providing the liquid supplyports 140A and the gas discharge ports 130A are restricted, then it ispossible to suppress the formation of the vortex flow, and it ispossible to prevent the gas (bubble) from staying in the liquid LQ inthe optical path space for the exposure light beam EL. The gas (bubble)can be discharged to the outside of the optical path space for theexposure light beam EL.

For example, the numbers and the arrangement of the liquid supply ports140A and the gas discharge ports 130A and the shapes of the flowpassages 181F, 182F corresponding to the liquid supply ports 140A andthe gas discharge ports 130A can be arbitrarily set provided that theformation of the vortex flow can be suppressed, and the gas (bubble) canbe discharged to the outside of the optical path space for the exposurelight beam EL. For example, a plurality of, i.e., four or more of theliquid supply ports 140A and the gas discharge ports 130A may beprovided. The numbers of the liquid supply ports 140A and the gasdischarge ports 130A may be different from each other. The liquid supplyports 140A and the gas discharge ports 130A may be arranged at unequalintervals. For example, it is preferable that the numbers and thearrangement of the liquid supply ports 140A and the gas discharge ports130A and the shapes of the flow passages 181F, 182F corresponding to theliquid supply ports 140A and the gas discharge ports 130A are optimizedon the basis of a result of an experiment or simulation so that theformation of the vortex flow can be suppressed, and the gas (bubble) canbe discharged to the outside of the optical path space for the exposurelight beam EL.

In the eighth to sixteenth embodiments described above, the liquidimmersion mechanism 1 makes the liquid LQ, supplied from the liquidsupply ports 140A provided at the first positions, to flow toward thegas discharge ports 130A provided at the second positions by the bottomplate portion (guide member) 172D. However, it is also allowable thatthe gas discharge ports 130A are absent at the second positions. Evenwhen the gas discharge ports 130A are absent, the gas portion (bubble),which exists in the optical path space for the exposure light beam EL,can be discharged to the outside of the optical path space for theexposure light beam EL by the flow of the liquid LQ. It is possible toprevent the gas from staying in the liquid LQ in the optical path spacefor the exposure light beam EL. On the other hand, when the gasdischarge ports 130A are provided at the second positions, it ispossible to smoothly discharge the gas from the optical path space forthe exposure light beam EL.

In the eighth to sixteenth embodiments described above, the liquidimmersion mechanism 1 supplies the liquid LQ in the Y axis direction tothe projection area AR1. However, for example, the liquid supply ports140A may be provided on the both sides, respectively, in the X axisdirection with respect to the projection area AR1, and the liquid LQ maybe supplied in the X axis direction to the projection area AR1.

In the first to sixteenth embodiments described above, the inclinedsurface (lower surface of the porous member), which is formed on thelower surface of the nozzle member 70, may be a curved surface. The wallportion 76 may be provided at the circumferential edge of the lowersurface 2 of the porous member 25 in the second to fourth embodimentsexplained with reference to FIGS. 9 to 11.

In the first to sixteenth embodiments described above, the porous member25 is arranged in the liquid recovery port 22. However, the porousmember 25 may be omitted. Even in such an arrangement, for example, whenan inclined surface, in which the distance with respect to the surfaceof the substrate P is increased at positions separated farther from theoptical axis AX of the exposure light beam EL, is provided on the lowersurface of the nozzle member 70, and the liquid recovery port isprovided at a predetermined position of the inclined surface, then theshape of the interface LG can be maintained, and it is possible to avoidthe inconvenience which would be otherwise caused, for example, suchthat the bubble is generated in the liquid LQ of the liquid immersionarea AR2. Further, the size of the liquid immersion area AR2 can bedecreased as well. In the first to sixteenth embodiments describedabove, the liquid recovery port is provided on the inclined surface(lower surface of the porous member) disposed on the lower surface ofthe nozzle member 70. However, it is also allowable that the inclinedsurface is not formed on the lower surface of the nozzle member 70, andthe liquid recovery port is provided on the surface which issubstantially parallel to (flush with) the land surface 75, providedthat the liquid immersion area AR2 of the liquid LQ can be maintained inthe desired state. That is, the liquid recovery port may be provided onthe surface substantially parallel to (for example, flush with) the landsurface 75, provided that the liquid LQ can be recovered without causingany leakage even when the movement velocity of the substrate P isincreased, for example, when the contact angle of the liquid LQ withrespect to the substrate P is large, and/or when the ability to recoverthe liquid LQ from the liquid recovery port 22 is high.

In the first to sixteenth embodiments described above, the wall portion76 is provided at the circumferential edge of the inclined surface(lower surface of the porous member) formed on the lower surface of thenozzle member 70. However, when the leakage of the liquid LQ can besuppressed, it is also possible to omit the wall portion 76. In thefirst to sixteenth embodiments described above, the groove 73 having theopening 73A opposed to the substrate P is provided for the nozzlemember. However, the groove 73 may be omitted. In this case, all of theliquid LQ on the side of the image plane of the projection opticalsystem PL may be recovered by using the liquid recovery port 22 in orderto provide the non-liquid immersion state for the space on the side ofthe image plane of the projection optical system PL. In this case, whenthe opening, which is connected to the space G2 between the opticalelement LS1 and the upper surface of the bottom plate portion 72D, isformed as in the sixth to sixteenth embodiments, the liquid LQ may berecovered from the opening concurrently with the liquid recoveryoperation to be performed with the liquid recovery port 22.

In the first to sixth embodiments described above, the nozzle member 70has the land surface (flat portion) 75 such that a portion thereof isformed between the projection optical system PL and the substrate P, andthe inclined surface (lower surface of the porous member 25) is formedat the outside thereof. However, a portion of the land surface may bearranged outside (around) the end surface T1 of the projection opticalsystem PL with respect to the optical axis of the projection opticalsystem PL, instead of arranging the portion of the land surface underthe projection optical system PL. In this case, the land surface 75 maybe substantially flush with the end surface T1 of the projection opticalsystem PL, or the position of the land surface 75 in the Z axisdirection may be separated in the +Z direction or in the −Z directionwith respect to the end surface T1 of the projection optical system PL.

In the first to fifth embodiments described above, the liquid supplyport 12 is formed to have the annular slit-shaped form to surround theprojection area AR1. However, a plurality of supply ports, which areseparated and away from each other, may be provided. In this case, thepositions of the supply ports are not specifically limited. However, thesupply ports may be provided one by one on the both sides of theprojection area AR1 (both sides in the X axis direction or both sides inthe Y axis direction). Alternatively, the supply ports may be providedone by one (four in total) on the both sides in the X axis direction andthe Y axis direction of the projection area AR1. Only one supply portmay be provided at a position separated in a predetermined directionfrom the projection area AR1, provided that the desired liquid immersionarea AR2 can be formed. When the liquid LQ is supplied from a pluralityof supply ports, then the amounts of the liquid LQ to be supplied fromthe respective supply ports may be made adjustable, and the liquid LQmay be supplied from the respective supply ports in different amounts.

In the first to sixteenth embodiments described above, the opticalelement LS1 of the projection optical system PL is a lens element havingthe refracting power. However, a plane parallel plate having norefracting power may be used as the optical element LS1.

In the first to sixteenth embodiments described above, the optical pathspace, which is disposed on the side of the image plane (lower surfaceside) of the optical element LS1 of the projection optical system PL, isfilled with the liquid LQ. However, it is also possible to adopt anarrangement in which the both optical path spaces disposed on the uppersurface side and the lower surface side, respectively, of the opticalelement LS1 of the projection optical system PL are filled with theliquid, as disclosed in International Publication No. 2004/019128.

As described above, pure water is used as the liquid LQ in theembodiment of the present invention. Pure water is advantageous in thatpure water is available in a large amount with ease, for example, in thesemiconductor production factory, and pure water exerts no harmfulinfluence, for example, on the optical element (lens) and thephotoresist on the substrate P. Further, pure water exerts no harmfulinfluence on the environment, and the content of impurity is extremelylow. Therefore, it is also expected to obtain the function to wash thesurface of the substrate P and the surface of the optical elementprovided at the end surface of the projection optical system PL. Whenthe purity of pure water supplied from the factory or the like is low,it is also allowable that the exposure apparatus is provided with anultra pure water-producing unit.

It is approved that the refractive index n of pure water (water) withrespect to the exposure light beam EL having a wavelength of about 193nm is approximately 1.44. When the ArF excimer laser beam (wavelength:193 nm) is used as the light source of the exposure light beam EL, thenthe wavelength is shortened on the substrate P by 1/n, i.e., to about134 nm, and a high resolution is obtained. Further, the depth of focusis magnified about n times, i.e., about 1.44 times as compared with thevalue obtained in the air. Therefore, when it is enough to secure anapproximately equivalent depth of focus as compared with the case of theuse in the air, it is possible to further increase the numericalaperture of the projection optical system PL. Also in this viewpoint,the resolution is improved.

When the liquid immersion method is used as described above, thenumerical aperture NA of the projection optical system is 0.9 to 1.3 insome cases. When the numerical aperture NA of the projection opticalsystem is large as described above, it is desirable to use the polarizedillumination, because the image formation performance is deteriorateddue to the polarization effect in some cases with the random polarizedlight which has been hitherto used as the exposure light beam. In thiscase, it is appropriate that the linear polarized illumination, which isadjusted to the longitudinal direction of the line pattern of theline-and-space pattern of the mask (reticle), is effected so that thediffracted light of the S-polarized light component (TE-polarized lightcomponent), i.e., the component in the polarization direction along withthe longitudinal direction of the line pattern is dominantly allowed tooutgo from the pattern of the mask (reticle). When the space between theprojection optical system PL and the resist coated on the surface of thesubstrate P is filled with the liquid, the diffracted light of theS-polarized light component (TE-polarized light component), whichcontributes to the improvement in the contrast, has the hightransmittance on the resist surface, as compared with the case in whichthe space between the projection optical system PL and the resist coatedon the surface of the substrate P is filled with the air (gas).Therefore, it is possible to obtain the high image formation performanceeven when the numerical aperture NA of the projection optical systemexceeds 1.0. Further, it is more effective to appropriately combine, forexample, the phase shift mask and the oblique incidence illuminationmethod (especially the dipole illumination method) adjusted to thelongitudinal direction of the line pattern as disclosed in JapanesePatent Application Laid-open No. 6-188169. In particular, thecombination of the linear polarized illumination method and the dipoleillumination method is effective when the periodic direction of theline-and-space pattern is restricted to one predetermined direction andwhen the hole pattern is clustered in one predetermined direction. Forexample, when a phase shift mask of the half tone type having atransmittance of 6% (pattern having a half pitch of about 45 nm) isilluminated by using the linear polarized illumination method and thedipole illumination method in combination, the depth of focus (DOF) canbe increased by about 150 nm as compared with the use of the randompolarized light provided that the illumination σ, which is prescribed bythe circumscribed circle of the two light fluxes for forming the dipoleon the pupil plane of the illumination system, is 0.95, the radius ofeach of the light fluxes at the pupil plane is 0.125σ, and the numericalaperture of the projection optical system PL is NA=1.2.

For example, when the ArF excimer laser is used as the exposure lightbeam, and the substrate P is exposed with a fine line-and-space pattern(for example, line-and-space of about 25 to 50 nm) by using theprojection optical system PL having a reduction magnification of about¼, then the mask M functions as a polarizing plate due to the Wave guideeffect depending on the structure of the mask M (for example, thepattern fineness and the thickness of chromium), and the diffractedlight of the S-polarized light component (TE-polarized light component)is radiated from the mask M in an amount larger than that of thediffracted light of the P-polarized light component (TM-polarized lightcomponent) which lowers the contrast. In this case, it is desirable touse the linear polarized illumination as described above. However, evenwhen the mask M is illuminated with the random polarized light, it ispossible to obtain the high resolution performance even when thenumerical aperture NA of the projection optical system PL is large, forexample, 0.9 to 1.3.

When the substrate P is exposed with an extremely fine line-and-spacepattern on the mask M, there is such a possibility that the P-polarizedlight component (TM-polarized light component) is larger than theS-polarized light component (TE-polarized light component) due to theWire Grid effect. However, for example, when the ArF excimer laser isused as the exposure light beam, and the substrate P is exposed with aline-and-space pattern larger than 25 nm by using the projection opticalsystem PL having a reduction magnification of about ¼, then thediffracted light of the S-polarized light component (TE-polarized lightcomponent) is radiated from the mask M in an amount larger than that ofthe diffracted light of the P-polarized light component (TM-polarizedlight component). Therefore, it is possible to obtain the highresolution performance even when the numerical aperture NA of theprojection optical system PL is large, for example, 0.9 to 1.3.

Further, it is also effective to use the combination of the obliqueincidence illumination method and the polarized illumination method inwhich the linear polarization is effected in the tangential(circumferential) direction of the circle having the center of theoptical axis as disclosed in Japanese Patent Application Laid-open No.6-53120, without being limited to only the linear polarized illumination(S-polarized illumination) adjusted to the longitudinal direction of theline pattern of the mask (reticle). In particular, when the pattern ofthe mask (reticle) includes not only the line pattern extending in onepredetermined direction, but the pattern also includes the line patternsextending in a plurality of different directions in a mixed manner(line-and-space patterns having different periodic directions arepresent in a mixed manner), then it is possible to obtain the high imageformation performance even when the numerical aperture NA of theprojection optical system is large, by using, in combination, the zonalillumination method and the polarized illumination method in which thelight is linearly polarized in the tangential direction of the circlehaving the center of the optical axis, as disclosed in Japanese PatentApplication Laid-open No. 6-53120 as well. For example, when a phaseshift mask of the half tone type having a transmittance of 6% (patternhaving a half pitch of about 63 nm) is illuminated by using, incombination, the zonal illumination method (zonal ratio: ¾) and thepolarized illumination method in which the light is linearly polarizedin the tangential direction of the circle having the center of theoptical axis, the depth of focus (DOF) can be increased by about 250 nmas compared with the use of the random polarized light provided that theillumination a is 0.95 and the numerical aperture of the projectionoptical system PL is NA=1.00. In the case of a pattern having a halfpitch of about 55 nm and a numerical aperture of the projection opticalsystem NA=1.2, the depth of focus can be increased by about 100 nm.

In the embodiment of the present invention, the optical element LS1 isattached to the end portion of the projection optical system PL. Such alens makes it possible to adjust the optical characteristics of theprojection optical system PL, for example, the aberration (for example,spherical aberration and comatic aberration). The optical element, whichis attached to the end portion of the projection optical system PL, maybe an optical plate which is usable to adjust the opticalcharacteristics of the projection optical system PL. Alternatively, theoptical element may be a plane parallel plate or parallel flat platethrough which the exposure light beam EL is transmissive.

When the pressure, which is generated by the flow of the liquid LQ, islarge between the substrate P and the optical element disposed at theend portion of the projection optical system PL, it is also allowablethat the optical element is tightly fixed so that the optical element isnot moved by the pressure, instead of allowing the optical element to beexchangeable.

In the embodiment of the present invention, the space between theprojection optical system PL and the surface of the substrate P isfilled with the liquid LQ. However, for example, it is also allowablethat the space is filled with the liquid LQ in such a state that a coverglass formed of a parallel flat plate is attached to the surface of thesubstrate P.

In the case of the projection optical system PL concerning each of theembodiments explained with reference to FIGS. 1 to 32, the optical pathspace, which is on the side of the image plane of the optical elementarranged at the end portion, is filled with the liquid. However, it isalso possible to adopt such a projection optical system that the opticalpath space, which is on the side of the mask M in relation to theoptical element LS1, is also filled with the liquid, as disclosed inInternational Publication No. 2004/019128.

The liquid LQ is water in the embodiment of the present invention.However, the liquid LQ may be any liquid other than water. For example,when the light source of the exposure light beam EL is the F₂ laser, theF₂ laser beam is not transmitted through water. Therefore, thosepreferably usable as the liquid LQ may include, for example,fluorine-based fluids such as fluorine-based oil and perfluoropolyether(PFPE) through which the F₂ laser beam is transmissive. In this case,the portion, which makes contact with the liquid LQ, is subjected to aliquid-attracting treatment by forming, for example, a thin film with asubstance having a molecular structure containing fluorine having smallpolarity. Alternatively, other than the above, it is also possible touse, as the liquid LQ, those (for example, cedar oil) which have thetransmittance with respect to the exposure light beam EL, which have therefractive index as high as possible, and which are stable against thephotoresist coated on the surface of the substrate P and the projectionoptical system PL. Also in this case, the surface treatment is performeddepending on the polarity of the liquid LQ to be used. It is alsopossible to use various fluids having desired refractive indexesincluding, for example, supercritical fluids and gases having highrefractive indexes, in place of pure water as the liquid LQ.

In the explanation with reference to FIGS. 1, 4, 15, 16, 18, 21, 22, and24, the space between the substrate P and the lower surface T1 of theoptical element LS1 is filled with the liquid LQ in the state in whichthe substrate P is opposed to the lower surface T1 of the opticalelement LS1. However, it goes without saying that any space between theprojection optical system PL and another member can be filled with theliquid as well, when the projection optical system PL is opposite to theanother member (for example, the upper surface 91 of the substratestage).

The substrate P, which is usable in the respective embodiments describedabove, is not limited to the semiconductor wafer for producing thesemiconductor device. Those applicable include, for example, the glasssubstrate for the display device, the ceramic wafer for the thin filmmagnetic head, and the master plate (synthetic silica glass, siliconwafer) for the mask or the reticle to be used for the exposureapparatus. In the embodiment described above, the light-transmissivetype mask (reticle) is used, in which the predetermined light-shieldingpattern (or phase pattern or dimming or light-reducing pattern) isformed on the light-transmissive substrate. However, in place of such areticle, as disclosed, for example, in U.S. Pat. No. 6,778,257, it isalso allowable to use an electronic mask on which a transmissivepattern, a reflective pattern, or a light-emitting pattern is formed onthe basis of the electronic data of the pattern to be subjected to theexposure. The present invention is also applicable to the exposureapparatus (lithography system) in which a line-and-space pattern isformed on a wafer W by forming interference fringes on the wafer W asdisclosed in International Publication No. 2001/035168.

As for the exposure apparatus EX, the present invention is alsoapplicable to the scanning type exposure apparatus (scanning stepper)based on the step-and-scan system for performing the scanning exposurewith the pattern of the mask M by synchronously moving the mask M andthe substrate P as well as the projection exposure apparatus (stepper)based on the step-and-repeat system for performing the full fieldexposure with the pattern of the mask M in a state in which the mask Mand the substrate P are allowed to stand still, while successivelystep-moving the substrate P.

As for the exposure apparatus EX, the present invention is alsoapplicable to the exposure apparatus based on the system in which thefull field exposure is performed on the substrate P by using aprojection optical system (for example, the dioptric type projectionoptical system having a reduction magnification of ⅛ and including nocatoptric element) with a reduction image of a first pattern in a statein which the first pattern and the substrate P are allowed tosubstantially stand still. In this case, the present invention is alsoapplicable to the full field exposure apparatus based on the stitchsystem in which the full field exposure is further performed thereafteron the substrate P by partially overlaying a reduction image of a secondpattern with respect to the first pattern by using the projectionoptical system in a state in which the second pattern and the substrateP are allowed to substantially stand still. As for the exposureapparatus based on the stitch system, the present invention is alsoapplicable to the exposure apparatus based on the step-and-stitch systemin which at least two patterns are partially overlaid and transferred onthe substrate P, and the substrate P is successively moved.

The present invention is also applicable to the twin-stage type exposureapparatus. The structure and the exposure operation of the twin-stagetype exposure apparatus are disclosed, for example, in Japanese PatentApplication Laid-open Nos. 10-163099 and 10-214783 (corresponding toU.S. Pat. Nos. 6,341,007, 6,400,441, 6,549,269, and 6,590,634),Published Japanese Translation of PCT International Publication forPatent Application No. 2000-505958 (corresponding to U.S. Pat. No.5,969,441), and U.S. Pat. No. 6,208,407, contents of which areincorporated herein by reference within a range of permission of thedomestic laws and ordinances of the state designated or selected in thisinternational application.

The present invention is also applicable to the exposure apparatusincluding a substrate stage which holds the substrate P and a measuringstage which is provided with various photoelectric sensors and referencemembers formed with reference marks, as disclosed in Japanese PatentApplication Laid-open No. 11-135400.

As for the type of the exposure apparatus EX, the present invention isnot limited to the exposure apparatus for the semiconductor deviceproduction for exposing the substrate P with the semiconductor devicepattern. The present invention is also widely applicable, for example,to the exposure apparatus for producing the liquid crystal displaydevice or for producing the display as well as the exposure apparatusfor producing, for example, the thin film magnetic head, the imagepickup device (CCD), the reticle, or the mask.

When the linear motor is used for the substrate stage PST and/or themask stage MST, it is allowable to use any one of those of the airfloating type based on the use of the air bearing and those of themagnetic floating type based on the use of the Lorentz's force or thereactance force. Each of the stages PST, MST may be either of the typein which the movement is effected along the guide or of the guidelesstype in which no guide is provided. An example of the use of the linearmotor for the stage is disclosed in U.S. Pat. Nos. 5,623,853 and5,528,118, contents of which are incorporated herein by referencerespectively within a range of permission of the domestic laws andordinances of the state designated or selected in this internationalapplication.

As for the driving mechanism for each of the stages PST, MST, it is alsoallowable to use a plane motor in which a magnet unit provided withtwo-dimensionally arranged magnets and an armature unit provided withtwo-dimensionally arranged coils are opposed to one another, and each ofthe stages PST, MST is driven by the electromagnetic force. In thiscase, any one of the magnet unit and the armature unit may be connectedto the stage PST, MST, and the other of the magnet unit and the armatureunit may be provided on the side of the movable surface of the stagePST, MST.

The reaction force, which is generated in accordance with the movementof the substrate stage PST, may be mechanically released to the floor(ground) by using a frame member so that the reaction force is nottransmitted to the projection optical system PL. The method for handingthe reaction force is described in detail, for example, in U.S. Pat. No.5,528,118 (Japanese Patent Application Laid-open No. 8-166475), contentsof which are incorporated herein by reference within a range ofpermission of the domestic laws and ordinances of the state designatedor selected in this international application.

The reaction force, which is generated in accordance with the movementof the mask stage MST, may be mechanically released to the floor(ground) by using a frame member so that the reaction force is nottransmitted to the projection optical system PL. The method for handingthe reaction force is described in detail, for example, in U.S. Pat. No.5,874,820 (Japanese Patent Application Laid-open No. 8-330224), contentsof which are incorporated herein by reference within a range ofpermission of the domestic laws and ordinances of the state designatedor selected in this international application.

As described above, the exposure apparatus EX according to theembodiment of the present invention is produced by assembling thevarious subsystems including the respective constitutive elements asdefined in claims so that the predetermined mechanical accuracy, theelectric accuracy, and the optical accuracy are maintained. In order tosecure the various accuracies, those performed before and after theassembling include the adjustment for achieving the optical accuracy forthe various optical systems, the adjustment for achieving the mechanicalaccuracy for the various mechanical systems, and the adjustment forachieving the electric accuracy for the various electric systems. Thesteps of assembling the various subsystems into the exposure apparatusinclude, for example, the mechanical connection, the wiring connectionof the electric circuits, and the piping connection of the air pressurecircuits in correlation with the various subsystems. It goes withoutsaying that the steps of assembling the respective individual subsystemsare performed before performing the steps of assembling the varioussubsystems into the exposure apparatus. When the steps of assembling thevarious subsystems into the exposure apparatus are completed, theoverall adjustment is performed to secure the various accuracies as theentire exposure apparatus. It is desirable that the exposure apparatusis produced in a clean room in which, for example, the temperature andthe cleanness are managed.

As shown in FIG. 33, a microdevice such as a semiconductor device isproduced by performing, for example, a step 201 of designing thefunction and the performance of the microdevice, a step 202 ofmanufacturing a mask (reticle) based on the designing step, a step 203of producing a substrate as a base material for the device, an exposureprocess step 204 of exposing the substrate with a pattern of the mask byusing the exposure apparatus EX of the embodiment described above, astep 205 of assembling the device (including a dicing step, a bondingstep, and a packaging step), and an inspection step 206.

INDUSTRIAL APPLICABILITY

According to the present invention, the liquid immersion area of theliquid can be maintained in the desired state even when the scanningvelocity is increased to be high. Therefore, the exposure process can beperformed satisfactorily and efficiently.

1. An immersion exposure apparatus for exposing a substrate withexposure light via liquid, comprising: a projection optical systemhaving an optical axis and comprising a lens, the lens being disposed atan end portion on the side of the image plane of the projection opticalsystem, having refracting power, and having a light-receiving surfacearranged to receive the exposure light, a side surface and alight-emitting surface arranged to transmit the exposure light to aprojection area; and a supporting member which supports the lens; anozzle member arranged in the vicinity of and around the lens, providedto be at a position above the substrate and configured to form animmersion area on the substrate with the liquid such that the liquid ofthe immersion area is in contact with the light-emitting surface of thelens, the nozzle member having: a liquid supply port; a liquid recoveryport; a lower surface, in which an opening is formed so as to allow theexposure light to pass to the substrate; and an inclined inner sidesurface which is opposed to the side surface of the lens with a gapthere between, wherein: the supporting member supports the lens abovethe gap, the supply port is provided between the lower surface and therecovery port, and the inner side surface having an angle of inclinationcorresponding to the side surface of the lens so that the distance fromthe surface of the substrate is increased at positions separated fartherfrom the optical axis.
 2. The immersion exposure apparatus according toclaim 1, wherein the lens has a width that decreases towards the lightemitting surface.
 3. The immersion exposure apparatus according to claim1, wherein the lens is arranged such that the light-receiving surface ofthe lens crosses the optical axis.
 4. The immersion exposure apparatusaccording to claim 1, wherein the lens is arranged such that thelight-emitting surface of the lens crosses the optical axis.
 5. Theimmersion exposure apparatus according to claim 1, wherein a patternimage is projected in a projection region with the exposure light viathe projection optical system and liquid for a scanning exposure of thesubstrate, wherein a first width of the projection region in a firstdirection perpendicular to an optical axis of the projection opticalsystem is narrower than a second width of the projection region in asecond direction perpendicular to the first direction and the opticalaxis, and wherein the substrate is moved relative to the projectionregion during the scanning exposure with respect to the first direction.6. A device manufacturing method comprising: exposing a substrate usingthe immersion exposure apparatus according to claim 1; and processingthe exposed substrate.
 7. An immersion exposure method of exposing asubstrate with exposure light via liquid, comprising: arranging thesubstrate below a projection optical system comprising a lens supportedby a supporting member, the lens being disposed at an end portion on theside of the image plane of the projection optical system, havingrefracting power and having a light-receiving surface arranged toreceive the exposure light, a side surface and a light-emitting surfacearranged to transmit the exposure light to a projection area; andirradiating the exposure light onto the substrate via the projectionoptical system and an immersion area formed on the substrate with liquidby a nozzle member arranged in the vicinity of and around the lens andprovided at a position above the substrate, the liquid of the immersionarea being in contact with the light-emitting surface of the lens, thenozzle member having: a liquid supply port; a liquid recovery port; alower surface, in which an opening is formed so as to allow the exposurelight to pass to the substrate; and an inclined inner side surface whichis opposed to the side surface of the lens with a gap there between,wherein: the supporting member supports the lens above the gap, thesupply port is provided between the lower surface and the recovery port,and the inner side surface having an angle of inclination correspondingto the side surface of the lens so that the distance from the surface ofthe substrate is increased at positions separated farther from theoptical axis.
 8. The immersion exposure method according to any one ofclaim 7, wherein a width of the lens decreases towards thelight-emitting surface.
 9. The immersion exposure method according toclaim 7, wherein the light-receiving surface of the lens crosses theoptical axis.
 10. The immersion exposure method according to claim 7,wherein the light-emitting surface of the lens crosses the optical axis.11. The immersion exposure method according to claim 7, wherein apattern image is projected in a projection region with the exposurelight via the projection optical system and liquid for a scanningexposure of the substrate, wherein a first width of the projectionregion in a first direction perpendicular to an optical axis of theprojection optical system is narrower than a second width of theprojection region in a second direction perpendicular to the firstdirection and the optical axis, and wherein the substrate is movedrelative to the projection region during the scanning exposure withrespect to the first direction.
 12. A device manufacturing methodcomprising: exposing a substrate using the immersion exposure methodaccording to claim 7; and processing the exposed substrate.